Doctors in the UK have allegedly prevented Nigeria's President Muhammadu Buhari from returning to his homeland due to health concerns. The 74-year-old leader 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, according to Sahara Reporters website.

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

People fear a power vacuum at a time when the country is marred by economic recession, terrorism, famine, widespread corruption and religious and ethnic tensions.

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.

Spokesperson Femi Adesina said in several statements that Buhari has been making phone calls to officials in Nigeria, including to former president, Chief Olusegun Obasanjo, on his 80th birthday on 5 March.

Before leaving Nigeria, Buhari appointed Vice President Yemi Osinbajo as acting president.

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