Senate spokesman, Aliyu Sabi said this at a press briefing in Abuja on Tuesday, February 7, 2017.

"We are in receipt of the second letter from Mr President where he is informing the senate that he is extending his vacation," Sabi said.

“This arose because in the first letter he did inform us that he will use that to see his doctors.

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“In this second letter he is informing the senate that he is extending his vacation because in the cause of that routine medical check up they were still some test his doctors still want to run.

“This is a constitutional provision and let me say it is within his prerogative to do so and we are in receipt of that letter accordingly.

“This is why we had to brief you so that we are now confirming that yes we are in receipt of that letter formally and we know that many things have been going on but this is our formal and official pronouncements to Nigeria on this particular subject matter,” the Senate spokesman added.

President Buhari embarked on a 10-day vacation to London on Monday, January 23, 2017.

A source at the presidency had announced that Buhari would return to Nigeria on Sunday, February 5, and resume his duties on Monday February 6.

But Femi Adesina disclosed on Sunday that President Buhari would prolong his stay in London pending the result of health tests.