His wafer-thin victory in the August 27 vote sparked deadly unrest and opposition accusations of voter fraud in the oil-rich country.
Bongo was installed for a second time as president on Tuesday, three days after the Constitutional Court dismissed his rival Jean Ping’s fraud claims.
“The President of the Republic issued a decree appointing Mr Emmanuel Issoze Ngondet as Prime Minister… and asked him to form an inclusive government,” a statement from the president’s office said.
Government spokesman Alain Claude Bilie-By-Nze said the make up of the new government might not be announced until Sunday.
“Since it is an inclusive government, consultations will take time,” he said.
Ping reacted to the appointment saying that talk of an inclusive government “changes nothing” and that (Bongo) “must go”, according to his campaign manager John Nambo.
Bongo’s family has exercised a long grip on power in Gabon with Ali Bongo taking over from his father Omar Bongo, who ruled for four decades, after his death seven years ago.
On Tuesday, Bongo pledged to ensure “equal opportunities” for all and to push through a 2025 programme that would deliver a flourishing economy.
“This is the path that will guide the government which I will name in a few days,” he vowed.
Bongo’s second mandate has received a cool reception from the African Union and the United Nations, while the European Union voiced regret that the vote count had not been transparent.
But Bongo on Tuesday said the “democratic process has been recognised by everybody, including foreign observers”.
In its final tally, the court ruled Bongo had won 50.66 percent of the vote and Ping 47.24 percent, extending Bongo’s lead to 11,000 votes over his opponent.