'Nigeria Deputy Has Full Powers'
Nigeria's vice-president has the right to perform all duties on behalf of the sick president without a formal transfer of power, a judge has ruled.
It is the first of four cases against President Umaru Yar'Adua, who has been in Saudi Arabia since November.
The justice minister welcomed the ruling, saying it showed there had been no power vacuum in his absence.
But analysts say it may not please some critics who want to see Vice-President Goodluck Jonathan become head of state.
Justice Daniel Abutu said Mr Jonathan would only be legally regarded as "acting president" if he had received written instructions to do so.
Correspondents say the issue is so sensitive because of the ruling party's system of alternating power between north and south.
Northern powerbrokers may be reluctant to see Mr Yar'Adua, a northerner, officially hand over power to Mr Jonathan, from the south, before the next scheduled presidential elections in 2011.
Justice Minister Michael Aondoakka said the ruling would allow cabinet ministers to get on with the business of governing.
He said there was now no justification for the other three cases - due before court on Thursday - to go ahead.
In one of the cases, rights lawyer and activist Femi Falana wants all decisions taken by the cabinet during the president's absence to be annulled.
In another, the Nigerian Bar Association is demanding that he hand over power formally to Mr Jonathan.
And a rights group wants Mr Yar'Adua declared "missing".
In his first public remarks since falling ill, Mr Yar'Adua told the BBC on Tuesday he was in constant contact with his deputy.
He said he was recovering and hoped to be able to return to Nigeria to resume his duties.
Doctors say the president is suffering from acute pericarditis - inflammation of the lining of the heart. He also has a long-standing kidney complaint.