Nigeria's opposition party, People's Democractic Party (PDP), said it was time for the president to reveal his medical condition.
PDP spokesman Kola Ologbodiyan said: "We need full disclosure about the president's health".
A statement by a presidential spokesperson, Garba Shehu, on Monday said, "In the course of the technical stop-over for aircraft maintenance in London on his way back from Washington last week, the president had a meeting with his doctor".
On his return, the President is expected to embark on a two-day State scheduled visit to Jigawa, which was postponed earlier as a result of the All Progressives Congress, APC's Ward Congresses.More news: Ryan Coogler Is Interested In A Female 'Black Panther' Spinoff
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President Buhari had to cut short his medical trip to the United Kingdom to arrive on Friday 11th May, instead of his initial arrival date of Saturday, May 12th.
This is at least the third medical trip Buhari has undertaken to the United Kingdom in 2018 alone. These calls have grown louder since he announced plans to seek re-election next year.
"President Buhari just loves flying around".
He flew out again on Tuesday, citing a request from his doctor, and pledged to be back in Nigeria on Saturday.