A former army general dissolved the national legislature, suspended the constitution and declared himself president Sunday, a day after his rebel forces took control of Bangui, the capital.
In a state radio address introducing himself as the country's new "head of state," Francois Bozize said his fighters seized power "because of the mismanagement of the country and its inability to carry out its domestic responsibilities."
"Our government is that of peace and national reconciliation," he added.
The rebels attacked Bangui on Saturday while President Ange-Felix Patasse was in Niger for a meeting of African heads of state.
Afterward, Patasse flew to Yaounde, Cameroon, where he remained Sunday at a hotel under tight security. He has not spoken publicly since the attack.
It was unclear how much fighting between rebels and government soldiers occurred.
Patasse fended off previous attacks with the help of Libyan troops and Congolese rebels. But the Libyans were replaced by regional peacekeepers, and the Congolese rebels withdrew before Saturday's attack. Patasse's government has accused neighboring Chad of backing Bozize.
The Central African Republic, a nation of about 3.6 million, is rich in gold, diamonds and uranium but has been hit by military revolts and uprisings since independence from France in 1960.
In his eight-minute radio address, Bozize promised a "quick reconstruction" of one of the world's poorest nations. He also promised to hold elections but did not specify when.