Nigerian President Muhammadu Buhari has said he has never been "so sick" as he has felt in recent weeks.
He was speaking to dignitaries in the capital, Abuja, after returning from seven weeks of medical leave in the UK.
His absence led to some anxiety in Nigeria with people speculating about the president's health.
Vice-President Yemi Osinbajo was left in charge and Mr Buhari's spokesperson has tweeted that he will formally return to power on Monday.
The 74-year-old flew into an air force base in the northern city of Kaduna from London on Friday morning.
Despite talking about how he felt, Mr Buhari did not reveal any details of his condition.
He did say he was "feeling much better now" but added that further medical checks would be required.
At the end of his nine-minute speech, Mr Buhari said that he deliberately came back towards the weekend "so that the vice-president will continue and I will continue to rest".
One of his advisers tweeted that he was joking and his office has clarified that the formal constitutional procedure for him to retake the reins of power will happen on Monday.