Prime Minister Gordon Brown said on Wednesday Britain would take further sanctions against Sudan if it did not act swiftly to stop violence in Darfur.
"It is urgent now that the international community reach an agreement on the appropriate response," Brown told parliament.
"We are prepared to take further sanctions against the government and against people in that region if they do not cease the violence, stop the militias and make sure that people have a decent living standard in a region that for too long has suffered from poverty, famine and war," he said.
International experts estimate 200,000 people have died as a result of ethnic and political conflict in Darfur since it flared in 2003, when mostly non-Arab rebels took up arms after accusing the central government of neglect.
Washington calls the violence genocide, and blames the government and its allied militia. Khartoum rejects the term and says only 9,000 have died.
After months of negotiations the Sudan government has agreed to a 26,000-strong U.N.-African Union Darfur force under a draft U.N. Security Council resolution.
But Khartoum said on Sunday it had reservations about the mandate for the force, which is needed to bolster 7,000 AU troops and police who have failed to stem the violence.
"Even before that process arrives there should be a cessation of violence on the ground and the president has a responsibility for making that happen," Brown said.
He said Britain would then be prepared to contribute emergency economic aid to the region.
The UN-AU force is unlikely to deploy before next year. The draft resolution would authorise recruitment for the force and Sudan has said most of the troops should be from Africa.
While Sudan does not need to agree to the resolution, member states would be concerned the government might obstruct the deployment or operations of the force if Khartoum objects to its mandate.
