The United Nations Security Council is unlikely to impose heavy sanctions on Sudan even if Khartoum fails to meet the body's demands to rein in marauding militiamen in Darfur, a senior British official said on Friday. He also said it would be impractical to expand the mandate of a small African Union force into a wider peacekeeping role. The force is now charged only with protecting ceasefire monitors. The U.N. Security Council has threatened Sudan with unspecified sanctions unless it shows by the end of August it has made progress disarming Arab militias in the western desert region where more than a million people have fled their homes. A senior official from Britain's Foreign Office said council members wanted to show they were serious about getting Sudan to cooperate, although heavy sanctions were not likely. "There is a range of views in the Security Council, but the natural centre of gravity is not the imposition of heavy duty sanctions on Sudan," he said. "There will be a consciousness that for the strength and health of the U.N., it needs to follow up," he said, adding options ranged from imposing a travel ban or asset freeze to more serious measures, such as a global arms or oil embargo. --More 2006 Local Time 1706 GMT