Experts from the International Criminal Court have arrived in Kigali to help transfer Democratic Republic of Congo warlord Bosco Ntaganda to the Netherlands to face trial, a US official said.

Ntaganda, who turned himself in at the US embassy in Rwanda on Monday, is expected to be transferred for trial at The Hague-based ICC within days.

"A team from the International Criminal Court (ICC) arrived in Kigali yesterday to make the logistical arrangements for Bosco Ntaganda's transfer to The Hague," a State Department official told AFP on Thursday.

"We are seeking to facilitate his request to be transferred to the ICC as quickly as possible."

But he gave no timetable for when Ntaganda would be flown out of Rwanda en route for the Hague where he faces charges of using child soldiers, keeping women as sex slaves and participating in the murder of at least 800 people in eastern DR Congo between 2002 and 2003.

ICC prosecutor Fatou Bensouda said Wednesday he is expected to be transferred within "a couple of days."

Rwandan President Paul Kagame said Thursday all support would be given to ensure Ntaganda's swift extradition.