Nigeria, May 12 -- A retired diplomat, Ibrahim Gambari, has been appointed Chief of Staff to President Muhammadu Buhari, according to presidential sources and the Emir of Ilorin, Ibrahim Sulu-Gambari.

The appointment has not been officially announced by the president.

Mr Gambari, 75, who was the first United Nation's Under-Secretary-General and Special Adviser to the Secretary-General on Africa, is said to be "awaiting an official letter of confirmation" as the Chief of Staff to President Muhammadu Buhari, according to multiple sources.

In a statement by his aide, Abdulazeez Arowona, the Ilorin emir thanked President Muhammadu Buhari "for appointing Professor Ibrahim Gambari as his new Chief of Staff."

The emir described the appointme...