The United Nations is to be allowed into Sudan to investigate atrocities against non-Arabs by pro-government militias in the western Darfur region.
One million people have fled their homes in Darfur
Foreign Minister Mustafa Ismail said the five-person UN delegation would arrive in the next two days.
Khartoum initially refused to let the visit take place.
Khartoum denies accusations from human rights groups of a campaign of terror in Darfur, involving murder, rape and mass abductions.
A separate UN mission, to assess the need for humanitarian aid in Darfur, has been postponed until next week after the Sudanese expressed concern about security.
Correspondents say UN officials privately blame delays in being allowed into Darfur on criticism of Khartoum's policy there by the UN emergency relief coordinator.
Relief coordinator Jan Egeland said villages were being looted and burnt down and food and seed supplies destroyed in a "scorched earth" policy.
But the UN official remains optimistic that the crisis can be resolved.
"If the government does their bit and we do our bit, we can still save lives," Mr Egeland told AFP news agency.
New figures show that the humanitarian crisis to be much worse than previously thought.
Around 10,000 people are also believed to have died in more than a year of fighting.
One million people are believed to have fled their homes and are displaced in Darfur - well above earlier estimates of around 700,000.
More than 100,000 people have fled across the border into Chad, but have continued to face cross-border raids.
UN officials have described the situation in Darfur as the "worst humanitarian crisis in the world today".
Aid agencies' access to the region had been restricted.
Under a recent truce agreed at the Chadian capital Ndjamena, the government and rebels pledged to guarantee safe passage for humanitarian aid to Darfur.
But the rebels have now accused government of violating the ceasefire, and are threatening to pull out of planned peace talks.
The UN has launched a $115m appeal for humanitarian aid for Darfur.