Sudan has suspended the work of a United Nations mission in the violent Darfur region after accusing the world body of transporting a rebel leader who opposes a recent peace deal.
A spokesman for the Sudanese foreign ministry, Jamal Ibrahim, said the ban would stay in place until the government received an "explanation" from the UN.
He said the ban was imposed because a UN helicopter had moved the rebel leader Suleiman Adam Jamous, who rejects the recently signed peace deal, without consulting the government in Khartoum. The ban will not affect two UN agencies, Unicef and the World Food Programme.
"He was picked up by the UN helicopter between el-Fasher and Musbat," Mr Ibrahim said, referring to areas in North Darfur.
"The authorities were not consulted, no permission was asked for, and it was clear negligence," he said, adding it was a "flagrant violation" of the sovereignty of Sudan.
The UN spokeswoman Radhia Achouri said the mission had not received any formal communication from the government. "We have also seen the media reports but we have not received any formal and official confirmation of this from the government of Sudan," she said.
Fighting broke out in the Darfur region in western Sudan in 2003. More than 2.5 million people have fled their homes and been forced into a series of squalid camps. An estimated 180,000 people have died.
A peace deal, overseen by the United States and the United Kingdom, was signed on 5 May in Abuja, Nigeria. But only one of the three main rebel groups signed the deal and, since then, the fighting has increased.
The breakthrough in the negotiations to end the three-year conflict came after Britain and America, who have been most active in attempting to end the ethnic cleansing of the black African population by militias alleged to be supported by the Islamic government, dispatched senior envoys to the peace talks.
The accord provides for a ceasefire and for the disarmament of the Janjaweed Arab militia, allied to the Khartoum government, who burntvillages and expelled the local population as the central authorities moved to crush a rebellion over land and grazing rights.
Although the rebels failed to win a place in central government, the agreement guarantees rebel factions the majority in Darfur's three state legislatures. It also contains provisions for the integration of rebel forces into the national army; a protection force for civilians; establishment of a reconstruction and development fund; and provisions to compensate war victims.
But the deal has not been welcomed by many of the refugees living in Darfur. Tens of thousands have demonstrated, at times violently, against it. They say it does not meet their basic demands of proper compensation for war victims or enough political posts and the rebels want to monitor the disarmament of the Janjaweed.
Mr Jamous was the humanitarian co-ordinator for the main rebel Sudan Liberation Army (SLA) before it split in November last year and was the main contact for the more than 14,000 aid workers in the region. He had been imprisoned by a Darfur rebel leader, Minni Minnawi, for opposing the peace deal. Mr Minnawi's faction of the SLA is the only rebel group which signed the agreement. UN officials and other rights groups had been involved in securing Mr Jamous' release.
Darfur is patrolled by a 7,000 strong African Union force which is struggling to keep a lid on the fighting.Reuse content