The United States called Thursday for sanctions against the leaders of strife in Central African Republic that is forcing the United Nations to consider sending thousands of peacekeepers. The call by the US ambassador to the United Nations, Samantha Power, added to international concern over anarchy in Central African Republic which some UN officials have warned risks degenerating into genocide. African nations have started sending troops to the country where rebels overthrew the president in March. A transitional government led by a former rebel has since lost control of the huge, impoverished state. Power said there must be a "swift deployment" of the full African force. She added, in a comment on her Twitter account, that the international community should be "imposing sanctions on perpetrators of violence." The call came after US Secretary of State John Kerry announced $40 million of financing for the African force. Kerry said the government was failing to control what he called an "increasingly sectarian" crisis. Rebels forced President Francois Bozize to flee in March. They were blamed for much of the violence that followed, but the crisis has degenerated into clashes between Christian and Muslim communities. There are currently about 2,500 African troops in Central African Republic and the number is scheduled to eventually reach 3,600. But diplomats and military experts say this will not be enough to end the chaos. France has led calls for UN troops to be sent. France's UN ambassador Gerard Araud warned the UN Security Council again on Wednesday that there is a risk of "massacres, mass violence, if the international community does not intervene." He said "horrifying" stories of killings and rapes were coming out of the country. The Security Council is expected to give the African force time to try to control events, diplomats said. The United States has not yet said publicly whether it would back a peacekeeping force. UN leader Ban Ki-moon said this week that up to 9,000 troops could be needed if the United Nations does intervene.