"He has until mid-noon on Wednesday to leave," said Foreign Ministry spokesman Ali al-Sadig.

"The reason is the latest statements issued by Mr. Pronk on his Web site regarding severe criticism of the Sudanese Armed Forces and the fact that he said the government of Sudan is not implementing the Darfur peace agreement," al-Sadig added.

He said the Foreign Ministry met with Pronk on Sunday and had informed him of its decision.

Pronk has previously had problems with the government because of comments he published on his Web log www.janpronk.nl. The latest blog entry said Darfur rebels had beaten the army in two major battles in the last two months.

He said generals had been sacked, morale was low and soldiers were refusing to fight in North Darfur. The army was furious and issued a statement on Friday calling Pronk a danger to the nation's security.

One army source said they were asking President Omar Hassan al-Bashir, the commander-in-chief of the army, to expel Pronk.

Pronk's spokeswoman declined comment. UN officials in New York were not immediately available to react to the decision.

Experts say 200,000 people have been killed and 2.5 million forced from their homes in 2-1/2 years of revolt in Darfur. Pro-government militias are accused of a campaign of rape, murder and pillage, which Washington calls genocide.

Rebel commander Jar el-Naby said from North Darfur that militias had attacked again on Saturday around 100 km (62 miles) northwest of Darfur's main town of el-Fasher, raping two girls and looting villages.

Khartoum denies genocide but the International Criminal Court is investigating alleged war crimes in the region.

Only one of three negotiating rebel factions signed a May peace accord brokered by the African Union. Many non-signatories formed a new alliance called the National Redemption Front (NRF) which renewed hostilities with the government in June.

Since the deal, violence has only escalated in Darfur with rebel infighting and NRF clashes with the government. Tens of thousands more have been displaced and dozens of people killed.

Al-Sadig said rebels would consider Pronk's comments as encouragement to continue their military campaign.

The Darfur conflict has spilled over the border into Chad where tens of thousands of civilians have been forced to flee militia attacks from Darfur.