“I was appointed unanimously by my peers,” Tiangaye told AFP, adding that he was awaiting an official appointment by President Francois Bozize.
“We chose Tiangaye unanimously. We all back him,” said leading opposition figure Martin Ziguele.
The new premier had led the opposition’s delegation to the talks in Gabonese capital Libreville, where three days of tough negotiations mediated by regional bloc Eccas produced an accord signed by the rebels, the ruling group and the democratic opposition.
The appointment marks the first political step towards resolving a conflict sparked on 10 December when Seleka rebels launched an armed offensive, sweeping from the lawless north of the Central African Republic southwards before stopping short of the capital Bangui.
To comply with the accord, which called for an immediate ceasefire, Bozize dismissed former premier Faustin Archange Touadera on Saturday, allowing for a member of the opposition to take his place.
Tiangaye is now faced with the challenge of forming a hodgepodge government representing not only the opposition and the governing party but also the Seleka coalition as well as other rebels who had signed prior peace deals.
A lawyer by training, he made a name for himself in the impoverished west African nation by defending Jean-Bedel Bokassa, the former self-proclaimed emperor, and by arguing for Rwanda before the International Criminal Court.
He is a former head of the Central African Human Rights League, ex-president of the national transition council set up after Bozize swept into power in a 2003 coup and one of the main authors of the constitution adopted the following year.
The Central African Republic has been notoriously unstable since its independence from France in 1960.