Nigeria's federal court has ordered the country's government to decide in the next two weeks whether the ailing President is fit to lead the country.
President Umaru Yar'Adua has not been seen publicly since leaving Nigeria to be treated for a heart ailment in a hospital in Saudi Arabia almost two months ago.
The Federal High Court ruled that cabinet should hear testimony from five doctors, one of whom should be the president's personal physician, the BBC reports.
If cabinet decides that the president is not fit to carry out his duties, the vice-president would take over, the court ruled.
The court was responding to a law suit brought by opposition activist Farouk Adamu Aliyu who had asked for the judges to sack the president over his failing health and for failing to abide by the provisions of the constitution.
On Thursday, about 1,000 demonstrators marched in Lagos to protest about the president's prolonged absence.
The organisers of the protest say that, under the constitution, he should have handed over executive powers to his deputy.