sentences:  After the UN and Western governments refused his requests for aid and Lumumba stated that he was open to any country, including the Soviet Union, for assistance in the crisis, the U.S. and Belgium became wary and oversaw his removal from office by Kasa-Vubu on 5 September and ultimate execution by Belgian-led Katangese troops on 17 January 1961.On 25 November 1965, Army Chief of Staff Joseph-Désiré Mobutu, who later renamed himself Mobutu Sese Seko, officially came into power through a coup d'état.In 1971, he renamed the country Zaire.