The US on Sunday called for Germany to send ground troops to northern Syria, pushing Berlin to ramp up its military involvement in the fight against the Islamic State (IS) group as Washington looks to withdraw from the region.

"We want ground troops from Germany to partly replace our soldiers" in the area as part of the anti-IS coalition, US special representative on Syria James Jeffrey told German media including the Die Welt newspaper.

Jeffrey, who was visiting Berlin for Syria talks, added that he expects an answer this month.

Last year US President Donald Trump declared victory against IS and ordered the withdrawal of all 2,000 US troops from Syria. 

But a small number have remained in northeastern Syria, an area not controlled by the regime of President Bashar al-Assad, and Washington is pushing for increased military support from other members of the international coalition against IS.

"We are looking for volunteers who want to take part here and among other coalition partners," Jeffrey said.

Washington has two goals in the region: to support the US-backed Kurdish forces that expelled IS from northern Syria as they are increasingly threatened by Turkey, and to prevent a potential IS resurgence in the war-torn country.