Nigeria's President Muhammadu Buhari has decreased his working hours due to a prolonged illness, officials have claimed. The 74-year-old leader resumed office earlier in March, after spending 51 days on sick leave in the UK.

Buhari returned to Nigeria on 10 March, ending rumours he was too ill to travel back home. It seems however, the leader is still too unwell to resume his usual work pace.

Officials have claimed the leader spends between one and four hours per day at his office. This is sparking fears Buhari might not be able to carry out economic reforms needed in the country, hit by recession.

"Things are slowing down, particularly on the economic front, which is a concern," one Western diplomat, who was not named, was quoted by Reuters as saying.

A presidential source also confirmed the leader is due to travel back to the UK to undergo further medical treatment in April.

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 have not commented 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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