The UN team was blocked by the Sudanese government in Khartoum from visiting Darfur, but spoke to refugees and aid workers from the region.

The five UN team members travelled to neighbouring Chad, to where many refugees have fled, and where the war itself is spreading.

There they heard reports backing up well-established accusations of serious abuses in Darfur, including mass rape, abduction, and forcing people from their homes.

"There are gross violations of human rights and international humanitarian law, the government is complicit in those crimes with the Janjaweed militia that it arms and trains," said the head of the mission, Nobel peace prize winner Jody Williams.

The Arab militia known as the Janjaweed have been accused of attacking villagers in Darfur, killing inhabitants and forcing others to flee, while the government provides air support.

The government denies the allegation, and accuses the West of exaggerating the problems in Darfur.

The Sudanese ambassador to the UN, Ibrahim Margani Ibrahim Mohammed Kheir, told the BBC that Sudan was co-operating with the UN, and that the situation in Darfur was improving.

'Hollow threats'

The report is the latest in a series by the UN and other international bodies to document large-scale attacks on civilians, and to demand an international response.

Ms Williams said the atrocities detailed in the report were not new. But the investigators were framing the document in a way that was meant to demand action.

It stated that if a state was failing to protect its own citizens, "then the international community has to step up to the plate and assume its responsibilities," Ms Williams told BBC News.

So far, the international response had been "pathetic", she said.

"There are so many hollow threats towards Khartoum, that if I were Khartoum I wouldn't pay any attention either," she said.

"It is more than a tragedy. It was after Rwanda that people said 'never again', and here we are again... and the world sits by."

Censure motion

The continuing conflict will top the Human Rights Council's three-week session in Geneva.

The UN human rights commissioner Louise Arbour is known to be especially concerned at Sudan's lack of co-operation with the team.

She has described such obstruction as an affront which must be addressed.

European members of the council are thought to be planning a motion of censure against Sudan, but this is likely to be resisted by many African nations.

The UN human rights council is less than a year old.

It was created to replace the widely discredited human rights commission and action on Darfur is regarded as a key test of the council's credibility.

Up to now the council has censured only one country - Israel - for its actions in Lebanon and Gaza, prompting critics to say the new body is just as politicised and ineffective as the old one.

Crowds of children chanted their welcome to the UN's new humanitarian chief as he arrived in the rebel stronghold of Jebel Marra, west Darfur.

It was a very different scene to Saturday when Mr Holmes was barred from entering a camp for displaced people in north Darfur by the Sudanese military, though they later apologised.

But the message from some of the tens of thousands of people caught up in this four-year conflict is that they feel cut off.

One woman told me they feel insecure because, she says, the government has blocked the roads. She explains people here fear further attacks.

'Fragile morale'

Restrictions on the roads are also limiting the access of aid agencies. Medical, food and water supplies are struggling to get through.

The UN's new envoy warned that morale amongst humanitarian staff was now fragile and said it could take only one major incident to trigger a humanitarian collapse - an issue Mr Holmes is expected to raise with Sudanese ministers when he meets them on Monday.

"I hope the fact that I'm new can enable me to make a bit of a new start with the Sudanese government here.

"That's what I'm trying to do. And if I can make some forward progress on that basis so much the better," Mr Holmes said.

Winning security guarantees from the Sudanese authorities is bound to be hard, not least because the international community is again talking tough, threatening sanctions on Sudan.

"We are outgunned, we are outnumbered and we can be overrun very quickly," Gen Agwai told the delegation of statesmen, led by Archbishop Desmond Tutu.

The "Elders" have been visiting Darfur to try to find solutions to the conflict.

Rebels blamed

Gen Agwai said the AU detachment at the base in Haskanita had been caught off guard as they were conducting dusk prayers.

He said no African country could provide enough properly equipped troops for the mission in Darfur.

The African Union is reviewing the force's mandate to allow it more scope to protect itself.

Gen Agwai said he did not expect any improvement in the situation on the ground in Darfur until next year when a 26,000-strong joint AU-UN force is to be deployed under his command.

Darfur rebels are being blamed for the Haskanita attack but it is not clear which of the many groups carried it out.

The UN Security Council has condemned the attack but council members wrangled over the language of their statement.

South Africa wanted it called a terrorist attack but the US, Britain and France urged caution on naming those who might be behind the killings, saying it is not yet clear who carried them out, says the BBC's Laura Trevelyan at the UN in New York.

The UN and the AU are investigating the attack.

At least 200,000 people have died and some 2m forced from their homes during the four year conflict in Darfur.

And Foreign Secretary David Miliband said he hoped "common sense" would prevail in the case.

If convicted, Mrs Gibbons could face a prison sentence, a fine or 40 lashes.

She was arrested on Sunday in Khartoum after allowing her class of primary school pupils to name the teddy bear in September.

Muhammad is a popular name in mainly-Muslim Sudan, and a boy in Mrs Gibbons class has said he suggested to the class the teddy bear be named after himself.

'Chaotic' scenes

When she arrived at the building on Thursday Mrs Gibbons was taken with about 20 officers into one court before being ushered into another room - in scenes described as "chaotic" by BBC reporter Amber Henshaw.

Embassy officials and her legal team were initially not granted access to her, but were later allowed into the courtroom.

The hearing was expected to start at 2pm local time (1100 GMT), but appeared to have been delayed at least 45 minutes.

Meanwhile, in London Foreign Secretary David Miliband is due to meet the Sudan ambassador to discuss the case.

Before the meeting, he told reporters that he would express Britain's strong view that the incident was an "innocent misunderstanding" and hoped it would be resolved swiftly.

"The Sudanese legal system has to take its course but common sense has to prevail.

"It's not about disrespect for Sudan, it's about being absolutely clear that this is an innocent misunderstanding."

BBC world affairs correspondent Paul Reynolds said the British government was treating the case as a consular issue and not a diplomatic incident, with Mr Miliband's approach being to avoid confrontation with Sudan.

Khalid al Mubarak, of the Sudanese embassy in London, said Mrs Gibbons had sufficient support.

'Sensationalist' reporting

"Like all legal systems the judge can decide to dismiss the whole thing or that the case goes on anyway.

"Mrs Gibbons has consular support, the British embassy has one of the best solicitors in the country whom I know personally.

"There is no worry on that front at all. She will be very well represented and well treated."

Even though the British government has expressed concern about the arrest, Mr al Mubarak dismissed any suggestion that diplomatic relations had become strained, instead saying there had been "sensationalist" reporting.

'Unexpected'

"The general situation and relationship are very good now, with the exception of this minute and unexpected incident of Mrs Gibbons."

Sudan's top clerics have called for the full measure of the law to be used against Mrs Gibbons and labelled her actions part of a Western plot against Islam.

A Muslim youth organisation, the Ramadhan Foundation, called for Mrs Gibbons' immediate release.

Spokesman Mohammed Shafiq said: "This matter is not worthy of arrest or detention and her continued detention will not help repair the misconceptions about Islam."

A UK newspaper has published a letter from 80 Nobel laureates and artists urging Beijing to help end the conflict.

'Empty rhetoric'

Chinese foreign ministry spokesman Liu Jianchao said: "We have taken notice that recently there have been many controversies and actions involving China and Darfur.

"It is understandable if some people do not understand the Chinese government policy on Darfur, but I am afraid that some people may have ulterior motives, and this we cannot accept," he told a news conference.

"China is also concerned about the humanitarian situation in Darfur. [But] empty rhetoric will not help. We hope that relevant people will be more pragmatic."

Beijing says it has appointed a special envoy to Darfur and sent peacekeepers to the region. But many, including Steven Spielberg, say that is not enough.

At least 200,000 people have died and two million forced from their homes in the five-year conflict in Sudan's Darfur region, where pro-government militia are accused of widespread atrocities.

Sudan denies backing the Janjaweed militia and says the suffering in Darfur has been exaggerated.

Sudan sells some two-thirds of its oil to Beijing, while Beijing sells weapons to the Sudanese government and has blocked efforts to pressure Khartoum in the UN Security Council.

Campaigners say arms sold by China to the Sudanese government that have been used in Darfur.

'Ongoing failure'

Mr Spielberg's announcement late on Tuesday is Beijing's first big setback in staging the Olympics, analysts say.

The renowned director, who had been brought in as artistic adviser for the opening and closing ceremonies of the Games, said his conscience would not allow him to continue in the role.

"Sudan's government bears the bulk of the responsibility for these ongoing crimes, but the international community, and particularly China, should be doing more," he said.

Adding to the pressure, British newspaper the Independent has published on its front page the full text of a letter signed by 80 Nobel laureates, politicians and artists to Chinese President Hu Jintao urging greater action on Darfur.

Signatories include South Africa's Archbishop Desmond Tutu, US former Senator Bill Frist and British playwright Tom Stoppard, as well as a host of former Olympians.

The letter, released by campaigning group Crisis Action on 12 February, said China had both the opportunity and the responsibility to help bring peace to the troubled region.

"Ongoing failure to rise to this responsibility amounts, in our view, to support for a government that continues to carry out atrocities against its own people," the letter said.

But for Steven Spielberg it was still not enough.

His decision to withdraw as artistic adviser to the Games' opening and closing ceremonies will be seen as a huge blow.

Lucrative friendship

Beijing and Khartoum have long had strong political, economic and military ties.

China imports two-thirds of Sudanese oil - estimated at 500,000 barrels a day.

China is also believed to be Sudan's biggest arms supplier.

Because of this strong relationship, Chinese leaders have traditionally resisted international pressure to use their clout to bring peace to Darfur, where there is conflict between government-back militias and rebels.

Beijing has even used its veto at the UN Security Council - to block moves to impose sanctions on Sudan if it fails to stop the fighting in the troubled region.

China's stock response to outside criticism about its Darfur policy always used to be that other countries should not involve themselves in Chinese affairs.

More involvement

But last year Beijing made a slight adjustment to that policy, appointing an envoy to Darfur, Liu Guijin.

He is an experienced diplomat who knows Africa well, having served as ambassador to both Zimbabwe and South Africa.

China also agreed to send in peacekeepers to the region as part of a UN force.

A total of 135 soldiers, who will not be engaged in frontline duties, have already arrived in Darfur.

The London-based human rights organisation, Amnesty International, also claimed that China was selling weapons to Sudan in violation of a UN arms embargo.

Other human rights activists have called on countries to boycott the Beijing Olympics this August because of China's close relationship with Sudan.

And Hollywood star Mia Farrow voiced her own criticism, coining the phrase “genocide Olympics”, words that must have made Beijing officials shudder.

Olympic pressure

So China is currently attempting a delicate balancing act - trying to manage the expectations of the international community while maintaining close ties with Khartoum.

It adjusted its Darfur policy because it wants to be seen as a responsible player on the world stage, with a diplomatic stature to match its growing economic might.

More importantly, it does not want anything to impact on the Olympic Games.

It is not clear how Mr Spielberg's decision will affect the Olympics. But some analysts doubt it will lead to others cutting their links with the event.

“Most sponsors have anticipated this kind of an issue, are prepared to deal with it, and will continue to support the games,” said David Wolf, from media consultants Wolf Group Asia.

Chinese leaders will be hoping he is right.

As of May this year, the joint UN-African Union Darfur mission, Unamid, included nearly 9,600 uniformed personnel and about 1,300 civilian staff, both international and local.

It is not clear how many will be withdrawn. But Gen Martin Luther Agwai, Unamid force commander, said the peacekeepers would maintain their unit strength and would not stop patrolling.

"We will continue to protect the UN personnel and UN facilities that are here and we will continue to help the humanitarian organisations to continue to do their job of rendering humanitarian services to the people in Darfur," Gen Agwai said.

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A Sudanese official told the BBC that he had been informed by Unamid the evacuation would begin on Tuesday.

"This is a unilateral decision which the Sudanese government was not involved in," Mr Mutrif Seddeek told the BBC.

While clarifying that the ICC is an independent body over which it has no influence, the UN is nevertheless bracing itself for possible increased difficulties in western Sudan, the BBC's David Bamford reports.

But it is continuing to run, alongside other NGOs, large-scale humanitarian operations there and has thousands of peacekeepers in place, our correspondent notes.

Appeal for calm

On 8 July, seven Unamid peacekeepers were killed and 22 injured, seven critically, when they were attacked by heavily armed militia in northern Darfur.

Sudan's president was accused of genocide, crimes against humanity and war crimes in Darfur by ICC prosecutor Luis Moreno-Ocampo.

He told judges at The Hague that Omar al-Bashir bore criminal responsibility for alleged atrocities committed over the past five years.

Sudan has refused to hand over two suspects who Mr Moreno-Ocampo charged last year, Humanitarian Affairs Minister Ahmad Harun and militia leader Ali Kushayb.

It has also labelled Mr Moreno-Ocampo a criminal, and warned that any indictment could stall peace talks and cause mayhem in Sudan.

Sudanese cabinet minister al-Samani al-Wasila told the BBC the accusations were "politically motivated".

The White House urged all parties in Sudan to "remain calm", saying it would "monitor the situation" in The Hague.

US National Security Council spokesman Gordon Johndroe stressed that the US was not part of the ICC.

UK Prime Minister Gordon Brown urged Khartoum to co-operate with the ICC.

There was no immediate formal reaction from Russia or from China, which is Sudan's biggest arms supplier.

Some 300,000 people have died as a result of the conflict in Darfur since 2003 while more than two million people have fled their homes, the UN estimates.

Sudan's government denies mobilising Arab Janjaweed militias to attack black African civilians in Darfur since rebels took up arms in 2003.

"We're here to send a message to the world, we're people of peace, we want peace, we're the ones who make peace," said Mr Bashir.

Sudan's government has said it does not recognise the ICC or its decisions, and warned that any indictment could cause mayhem.

A three-judge panel at the ICC is currently considering whether there are reasonable grounds for any charges to be laid.

'Active participation'

In an interview with SABC-TV on Friday, President Mbeki said it was important that both the peace process in Darfur and the rebuilding of post-civil war Sudan were not disrupted by the ICC decision.

"Both of them require the very active participation of President Bashir," he said.

"I don't know how they would do that if an International Criminal Court says here's a person who has been indicted, because they then must stop interacting with him because this is a wanted criminal, and I don't know how you then implement all of those things," he added.

Mr Mbeki, who has been criticised for being soft on Zimbabwean President Robert Mugabe, said he was ready to meet Mr Bashir to discuss the implications.

The African Union has called for the UN Security Council to suspend the accusations, while the Arab League has warned they set a dangerous precedent.

ICC Chief Prosecutor Luis Moreno-Ocampo told judges at The Hague on 14 July that there were "reasonable grounds" for believing Mr Bashir bore criminal responsibility on 10 counts of genocide, crimes against humanity and war crimes in Darfur.

Some 300,000 people have died as a result of the conflict since 2003 while more than two million have fled their homes, the UN estimates.

Sudan's government denies mobilising Arab Janjaweed militias to attack black African civilians in Darfur after rebels took up arms.

But hanging over the agreement is a proposed indictment from the International Criminal Court of Sudan's President Omar al-Bashir for alleged crimes.

And other rebel groups are refusing to talk to the government.

'Remarkable progress'

The signing between the Sudanese government and the Jem rebels was announced by Qatari Prime Minister Sheikh Hamad bin Jassim al-Thani.

"I am very optimistic, as both sides are determined to end this conflict," the Qatari PM was quoted by AFP news agency as saying at a news conference after the signing.

BBC's Africa editor Martin Plaut says that by reaching this deal now, the government in Khartoum is signalling that it is moving on peace - under intense pressure from the international community.

Speaking to the BBC in New York, the Sudanese envoy to the UN described the agreement as "a very remarkable progress".

"It touches also on issues like security and safety of the IDPs [internally displaced people] and civilians, about which detailed discussions will be resumed in two weeks time," Abdalmahmood Abdalhaleem Mohamad said.

He rejected any suggestion that Sudan was trying to deflect attention away from the proposed ICC indictment of President Omar al-Bashir.

Jem spokesman Dr Eltahir Adam Elfaki told the BBC the key stumbling block of prisoner exchanges had been overcome.

"There was a big problem with the release of prisoners and those who have been convicted or detained by the Sudan government and by us," he told the BBC's Network Africa programme.

"Now that has been settled and both parties commit themselves to the release of the prisoners of war between the two parties.

"This will mean now both parties will stay in Doha, will start putting together the jigsaws for the actual framework agreement [that] will lead to the cessation of hostilities."

A Jem spokesperson in London, Haroun Abdul Hami, told the BBC's World Today programme: "The most important point is to stop the harassment of our people in the IDP camps in addition to [urging] the government not to impede the humanitarian aid to our people."

Last week Sudan's army said it had captured the strategic Darfur town of Muhajiriya after three weeks of clashes with rebels.

Thirty people were reported dead in that fighting, and a Jem rebel commander said his forces had withdrawn voluntarily to spare civilians from government air attacks.

The United Nations says at least 300,000 people have died and more than 2.2 million have been displaced since the conflict began six years ago.

Fighting started after African groups complaining of discrimination at the hands of Sudan's Arab-dominated government launched a rebellion.

The government admits mobilising "self-defence militias" in response, though it denies links to the Janjaweed, which has been accused of trying to "cleanse" black Africans from large swathes of territory.

The joint UN-African Union peacekeeping force, Unamid, remains at only about half its planned strength of 26,000, a year after the UN took joint control of the mission.

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