Nigeria's vice-president Goodluck Jonathan has become acting president, staving off the constitutional crisis brewing as a result of the leader's long absence.
President Umaru Yar'Adua has not been seen in public since going to Saudi Arabia in November for medical treatment.
The Nigerian constitution states that power is transferred to the vice-president when the president formally informs parliament of his absence, which Yar'Adua never did.
No-one has been in charge during this continued absence, triggering mass street protests, and political problems including a cabinet split and legal challenges.
There has been a freeze in government business, and a threat to efforts to tackle unrest in the turbulent Niger Delta region.
The National Assembly has now voted to recognise Jonathan as acting leader. He said in a speech: "I am fully aware of the responsibilities reposed in me, and I want to reassure all Nigerians that this is a sacred trust, which I shall discharge to my fullest abilities."
