He is due to return to Nigeria in the second week of this month, Femi Adesina said in a statement on Twitter.

Mr Buhari, 79, has regularly sought treatment abroad since he assumed the presidency in 2015.

He has often been criticised for seeking treatment outside the country while Nigeria’s healthcare system suffers from mismanagement and under-funding.

His time as president for two consecutive terms comes to an end in February when the country holds a general election.