Nigerian President Muhammadu Buhari failed to arrive for a weekly cabinet meeting on Wednesday, a Reuters reporter at the start of the session said, his third consecutive absence.
Vice President Yemi Osinbajo chaired the start of the session, which was open to the media, which had to leave after prayers were said and the national anthem played.
Buhari has been resting after treatment of an unspecific illness.
The 74-year-old former military ruler has hardly appeared in public since returning home in March after nearly two months' medical leave in Britain.
He did not attend the last two cabinet meetings.
Buhari had said on coming back from Britain that he would need more rest. Details of his medical condition were not disclosed.
On Tuesday, his wife Aisha Buhari, seeking to counter growning concerns about Buhari's ability to run the country, said his health was not a bad as assumed. She gave no details.
Osinbajo, a lawyer who is seen as more friendly to business than Buhari, has played an active role in driving policy changes, chairing cabinet meetings during the president's medical leave.