A court in Nigeria has ruled that President Muhammadu Buhari, 75, does not have to reveal the cost of the medical treatment he received in the UK last year.

A civil society group, Advocacy for Societal Rights Advancement and Development Initiative, brought the court action after the central bank refused to disclose his medical bill for his lengthy stay in the UK.

But Judge John Tsoho said the Freedom of Information Act contained exemptions, including in cases where individuals had not consented to the release of personal information, AFP reports.

"There is no evidence of the president having consented to disclosure of personal information relating to his health and the information is certainly not publicly available," the judge was quoted as saying.

"On the whole, the applicants' suit is not sustained and it is struck out," the judge added.

Mr Buhari made three medical trips to the UK last year, and one this year. He did not disclose his illness, but said: "I have never been so sick."

He seems to have recovered since then, and is running for a second four-year term in elections due next year.

At the time, a leading Nigerian doctor, Osahon Enabulele, accused Mr Buhari of reneging on a promise to end "medical tourism" by seeking treatment in the UK.