China plans to send an engineering unit to Sudan as part of a planned U.N. deployment to bolster the African Union peacekeeping force in Darfur, the U.S. State Department said on Monday.

The State Department welcomed the contribution, saying the team would number in the hundreds, but also called on China to use its influence with Sudan to accept the full U.N.-AU force, which Khartoum has resisted.

The U.N. Security Council in August approved a "hybrid" force of more than 20,000 troops and police to try to stop the violence in Darfur, where the United Nations says about 200,000 have died and 2.5 million have been displaced since 2003.

The conflict in Darfur, an ethnically mixed region of western Sudan, began when rebel groups took up arms against the government, accusing it of neglect.

Sudan agreed recently to a "heavy support package" for the African Union troops in Darfur that would include some 3,500 military and police personnel.

"We understand that China has decided to deploy an engineering unit as part of the U.N.-AU heavy support package in Darfur," said State Department spokesman Gonzalo Gallegos. "We understand that it will number in the hundreds."

"While participating in the heavy support package is a positive step, the real need is for the full deployment of the entire U.N.-AU force," Gallegos added. "We look to China to use its significant leverage in Khartoum to make this happen as soon as possible."

A U.S. official who spoke on condition he not be named said there would be about 300 people in the Chinese contingent.