A statement released by the Sudanese presidency on Saturday said all government agencies should mobilise "to control and pursue all outlaw groups, including rebels and Janjawid ..., disarm the outlaws and present them to justice and prevent any groups from crossing into neighbouring Chad".
The Janjawid is the local word for the Arab militias whom the Darfur rebels blame for much of the conflict in the region. The rebels say the government has backed the Janjawid but the government has repeatedly denied that.
International organisations have criticised the Sudanese government for failing to control the militias, who have driven hundreds of thousands of Africans out of their villages into camps for displaced persons or into exile in Chad.
Threat of sanctions
The United States threatened on Friday to impose sanctions on Sudanese officials as a way to intensify pressure on Khartoum to help ease the humanitarian crisis in Darfur.
The State Department is studying whether the militias are responsible for genocide in Sudan and if it can impose sanctions on individual officials, spokesman Adam Ereli told reporters.
Chad had complained of Janjawid
incursions into its territory
The Sudanese announcement implied a tougher line against the Janjawid and a more balanced policy towards the conflict.
Sudanese government officials have previously said it would be difficult to disarm the Arab militias as long as the two main rebel groups - the Sudan Liberation Movement and the Justice and Equality Movement - were active in the region.
The Sudanese president's order also answers Chadian complaints about Janjawid incursions into Chadian territory. A source close to Chadian President Idriss Deby said on Friday the Chadian army killed 69 Janjawid in a clash near the border on Thursday.
The presidential statement said that the judicial authorities in Darfur should set up prosecution offices and courts to prosecute plunder gangs and criminals "without delay".
Sudanese police should deploy to protect villages and enable displaced people to come home, it added.
Analysts say that part of the problem in Darfur is that the central government in Khartoum, 1000km from the Chad border, does not have the resources to control the area.