The wife of Nigeria's President Muhammadu Buhari, currently on medical leave in the UK, has said the vice-president is able to work towards the realisation of a better Nigeria. Aisha Buhari made the remarks as Vice President Yemi Osinbajo, who is currently acting as president, celebrated his 60th birthday on 8 March.

"I wish to extend my congratulations to you and to state that the years you have spent building your reputation in multiple capacities, have today resulted in your ability to carry out your duties in line with the manifesto of the [Buhari's party] All Progressives Congress (APC) to ensure that a better Nigeria is realised," Aisha said in a Twitter post.

The First Lady made headlines worldwide last year, after claiming her husband had failed to surround himself with people who shared APC objectives. The remarks prompted Buhari to claim his wife "belongs to the kitchen," a comment that attracted criticism.

Is President Buhari ill?

Buhari, 74, has been on medical leave in London since 20 January, amid rumours he is severely ill and unable to resume office.

It is believed the president was due to return to Nigeria on Sunday ( 5 March), but doctors refused to give him the clean bill of health that would enable him to leave,

Nigerians are becoming increasingly concerned with the president's health and have been calling on Buhari to personally dismiss allegations of ill health.

Buhari's stay in the UK is shrouded in mystery. The fact that top officials – including the president of the senate, Bukola Saraki – have travelled to London to visit the head of state is further fanning suspicions that the leadership is concealing his true condition.

The Nigerian Presidency has released several statements denying allegations of ill-health.

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