A spokesperson for Nigeria's President Muhammadu Buhari has denied claims the leader cancelled a planned medical trip to the UK. Earlier reports alleged the 74-year-old head of state, due to travel to London soon, decided to invite his doctors to Nigeria instead.

The Sahara Reporters website reported – citing unnamed presidential sources – the president was advised against leaving Nigeria, given the current economic crisis affecting the country.

But spokesperson Garba Shehu is now denying the allegations. "It is false news. We are not aware of the reported advance movements. The last time the president spoke about this, he said he would return to his doctors after some time. We are not aware that this has changed," he told the BBC.

Buhari already spent 51 days on medical leave in London earlier this year, amid fears he was too ill to continue to lead one of Africa's biggest economies.

He returned to Nigeria on 10 March, temporarily ending ill-health rumours. However, soon after, the presidency said the leader was planning to travel again in April for further medical tests.

Shehu's claims came one day after the federal government said it would not disclose Buhari's medical expenditure London, claiming the information was too sensitive, local media said.

Buhari's stay in the UK was shrouded in mystery, with many speculating the leader was not fit enough to resume office. However, the presidency always denied such allegations.

But some have claimed the leader is now working at a slow pace, meaning that economic reforms needed in the recession-hit country are not being implemented fast enough. Earlier this month, officials told Reuters Buhari now spends between one and four hours per day at his office.

Before leaving the country on 20 January, Buhari appointed Vice President Yemi Osinbajo as acting head of state.

Osinbajo has been praised for the leadeship skills he demonstrated during Buhari's absence, fuelling speculations he could have replaced Buhari if the latter had became incapacitated.

Buhari's spokespeople did not comment on the claims the president has reduced his working hours. Spokesperson Garba Shehu said on Twitter the president had been working from home "when most civil servants have closed".

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