In the letter, Buhari said that he will only return to Nigeria when his London doctors certify him well enough to do so.
The letter, dated February 5 2017, read:
Further to my letter dated 18th January 2017 in which I notified the Distinguished Senate of taking part of my annual leave.
During my leave, I took the opportunity to have routine check-ups and consult my long standing doctors in London.
In the course of the routine examinations, certain test result indicated the need for a course of medications and further appointments have been scheduled for next week.
I am therefore notifying the Distinguished Senate that I am extending my leave until the doctors are satisfied that certain factors are ruled out. In the circumstances, the vice president will continue to act on my behalf.
Please accept, Distinguished Senate President, the assurances of my highest consideration.
Buhari, who was supposed to return to Nigeria on February 5, wrote the National Assembly to extend his vacation to continue some tests.
Consequently, Vice President Yemi Osinbajo will continue as Acting President.