Arusha — Congolese rebel Bosco Ntaganda, wanted by the International Criminal Court for crimes against humanity, has been at the US embassy in Kigali since Monday, according to the Rwandan government.

US State Department spokesperson Victoria Nuland said earlier that Ntaganda had turned himself into the embassy and was asking to be sent to the ICC.

The ICC welcomed Ntaganda's surrender and said it was in contact with the relevant authorities to arrange for his transfer to The Hague.

Ntaganda is a Congolese Tutsi rebel who became a general in the Congolese government army in 2009 but defected again last year. Many experts say he was one of the leaders of the M23 rebellion launched in May 2012.

The ICC has issued two arrest warrants for Ntaganda since 2006 for crimes against humanity and war crimes. The charges against him include using rape as a weopon of war and conscripting child soldiers in Ituri (northeast Democratic Republic of Congo) and Kivu (eastern DRC) between 2002 and 2003. UN experts have recently accused Rwanda of supporting the M23, which Kigali has strongly denied.

Meanwhile, former Irish president Mary Robinson has been named UN Secretary General Ban Ki-moon's Special Envoy to the Great Lakes Region. Her main task will be to monitor the peace agreement signed by eleven countries in Addis Ababa in February.

In a statement, Ms Robinson called on the countries of the Great Lakes Region to cooperate with the ICC.