GENEVA, Jan 26 (Reuters) - Nobel peace laureate Jody Williams will lead a six-strong international mission to Sudan's Darfur region to investigate rights abuses against civilians, the head of the U.N. human rights watchdog announced on Friday. The mission was agreed to by the Geneva-based United Nation's Human Rights Council in December after a heated debate, but agreeing on the names took several weeks. Council chairman Luis Alfonso de Alba said Williams, co-winner of the Nobel Peace Prize in 1997 for her campaigning to ban landmines, would lead the team, which will travel to Darfur in early February. She will be joined by former deputy U.N. High Commissioner for Human Rights Bertrand Ramcharan, Estonian parliamentarian and racism expert Mart Nutt, Indonesia's ambassador to the U.N. in Geneva Makarim Wibisono and Patrice Tonda, Gabon's ambassador to the U.N. The U.N.'s special investigator on human rights in Sudan, Sima Samar, who has made several visits to the country, will also take part. The mission will report back to the Council at its March 12-April 5 session. Observers estimate that 200,000 people have died in four years of violence in Darfur, which Washington has called genocide. The conflict, which had its origins in tribal disputes over land, will feature at the African Union summit next week. The Sudanese government, which is accused of arming murderous militia groups, disputes the death toll and blames continuing violence on rebels who have refused a peace deal. Aid agencies say mounting attacks on their operations are crippling efforts to help civilians in Darfur, where over two million have been forced from their homes into squalid refugee camps. (Reporting by Richard Waddington, editing by Fredrik Dahl; e-mail: richard.waddington@reuters.com; tel: +41 22 733 3831))