Charges are to be dropped against two aid workers in Sudan's Darfur region accused of falsifying a report on rape, diplomats say.
Paul Foreman was arrested on Monday
The arrests led to an international outcry, which the BBC's Jonah Fisher in Khartoum says seems to have forced the Sudanese government into a u-turn.
Foreign Minister Mustafa Osman Ismail said he agreed that the pair should not have been arrested.
The Medecins Sans Frontieres report said nearly 500 women had been raped.
Two employees of MSF Holland - Vince Hoedt and Paul Foreman - have been charged over the report and could face up to three years in prison.
In the Netherlands, Sudan's ambassador was summoned to explain why his country were pressing charges against the heads of one of the aid agencies most prominent in helping the victims of two years of violence in Darfur.
The Sudanese authorities deny accusations that they back the Arab Janjaweed militias alleged to have committed widespread atrocities, such as mass killings and mass rape.
They also deny that the scale of the violence is as severe as reported by aid agencies.
In Khartoum, United Nations special envoy Jan Pronk met both the president and foreign minister.
He is said to have received assurances that all charges would be dropped.
But our correspondent says that, having made such an example of MSF, the government has asked for a few days to arrange the climb-down.
After meeting Mr Pronk, Mr Ismail refused to confirm that charges would be dropped, but said a resolution was in sight.
"We agreed on two things: that these people should not be arrested, they are not now in custody, they have been released," he said.
MSF say they have not been told of the dropping of charges, but said there was no question of them either denying the report or providing the confidential medical records to back it up.
Some two million people have fled their homes in Darfur
The BBC's Martin Plaut, who recently travelled to Darfur, says that many Sudanese believe Western aid workers have given information on alleged human rights abuses in Darfur to the United Nations, which has passed a sealed list of 51 war crimes suspects to the International Criminal Court.
On Tuesday, Mr Pronk condemned the "smear campaign" in Sudanese newspapers against aid workers, accusing them of fabricating reports of rape.
"MSF Holland and all the other MSF have saved many lives of Sudanese people," he said.
Human Rights Watch Africa director Peter Takirambudde said Mr Foreman's arrest was "a perfect illustration of how far the Sudanese government is prepared to go to silence criticism and deny its own responsibility for massive atrocities in Darfur."
MSF says it has a significant presence in Darfur, with some 180 international staff and 3,000 local staff treating some one million patients.
The UN says that about 180,000 people have died in the two-year conflict in Darfur, and more than two million driven from their homes.