(Adds U.N. response, paragraph 5) By Opheera McDoom KHARTOUM, Aug 13 (Reuters) - Darfur rebel figure Suleiman Jamous said on Monday if the United Nations did not respond to his request to fly him out of Sudan for medical treatment by Thursday, he would hand himself over to the government. Jamous, the Sudan Liberation Army's humanitarian coordinator, was the key liaison between insurgents and the world's largest aid operation helping some 4.2 million people in Darfur. "I gave them until Thursday," Jamous said. "If they refuse to take me out, I will just go out to where the government of Sudan is waiting to be detained, and I will consider this a compulsory turning over to the government by the U.N.," he told Reuters by telephone. In New York, U.N. spokeswoman Michele Montas said the world body was "concerned" about Jamous' situation and would respond shortly. But U.N. sources in Khartoum said it was unlikely that Jamous would be flown out of Sudan. The United Nations moved him to a U.N. hospital near Darfur more than a year ago without informing Khartoum. Sudan calls him a criminal and has said it would arrest him if he left U.N. care. Last week Sudan said Jamous could be released for peace talks, but declined to say whether his freedom would be conditional. Jamous needs a stomach biopsy which cannot be performed in the U.N. hospital. On Monday he left the hospital for the first time in more than 13 months to walk to the nearby U.N. headquarters and ask to be flown out of Sudan for medical treatment. "They replied they needed time to consult with Khartoum and I have given them until Thursday," Jamous said. "Now I am becoming indifferent. If I am detained by the United Nations or the government of Sudan it is the same." The elderly Jamous is respected in Darfur and considered a consensus builder who could help peace efforts and unify fractured rebels. Since a 2006 peace deal signed by only one of three negotiating rebel factions, the insurgents have split into more than a dozen groups, creating chaos in Darfur. Because of increasingly violent attacks against their staff and aid convoys, the humanitarian operation has been scaled down and some 500,000 people are out of reach of vital help. International experts estimate some 200,000 have been died and 2.5 million driven from their homes in more than four years of fighting in Darfur. (Additional reporting by Evelyn Leopold in New York)
