The United Nations has criticised the Sudanese government's use of red tape to delay the deployment of the hybrid UN-African Union force to Darfur.
Shops in Muhajiriya market were burned to the ground on Monday
In a highly critical report, UN Secretary General Ban Ki-moon accused Khartoum of failing to approve a list of troop-contributing countries.
He also said the UN was being prevented from obtaining land for offices and accommodation in Darfur.
Mr Ban said there was an unacceptable upsurge of violence in Darfur.
Some two million have been displaced and at least 200,000 have died during the four-year conflict and there is growing pessimism about the prospects for peace talks later this month.
"The ongoing loss of life and displacement of civilians is unacceptable and is not contributing to an atmosphere conducive for the peace talks in Libya," he said.
He adds that it is of critical importance that the Sudanese government extend the support and co-operation necessary to resolve issues pertaining to land, landing rights for UN aircraft and finalises the list of countries contributing troops.
Earlier this week, the UN issued a list of 15 nations, most of them African, as proposed troop contributors to the proposed 26,000-strong peacekeeping force.
But the UN is finding it difficult to obtain Khartoum's consent.
The timetable for getting the force up and running by the end of this year appears to be slipping, and the full force will not be in operation until well into 2008, observers say.
Meanwhile, the UN said dozens of people were killed in Monday's attack on the town of Muhajiriya in south Darfur.
In a statement, the UN said a large number of houses in the town were burnt to the ground, as were shops in the market.
The former rebels who signed last year's Darfur peace agreement accused the government of being behind the incident. The government denies this.
An estimated 6,000 villagers fled to the north while thousands more have dispersed to other nearby areas.
Reports from the town said dead bodies were strewn across the streets.
The attack came just days after armed men attacked the African Union base in nearby Haskanita - killing 10 AU soldiers.