Nigerian media are reporting that President Muhammadu Buhari's campaign for re-election has received a boost from unlikely quarters - namely the son of a former president.

Unlike ex-President Olusegun Obasanjo who last year called on the current president to step down at the end of his term, his son Olujonwo Obasanjo has declared his support for Mr Buhari and leads the Buhari Youth Organisation, the reports say.

"We have Buharists in the United States and all over the world," he is quoted by the Vanguard newspaper as saying.

Mr Obasanjo junior is reportedly in the United States drumming up support among the Nigerian diaspora.

"[Mr Buhari] is the one who has made us believe again in our country, who has made us proud of our country," he said, adding that the 76-year-old president "has opened up the space for the youth of the country to participate politically, economically."

Atiku Abubakar, who served as vice-president from 1999 to 2007, is Mr Buhari's main rival in the 16 February election.