President Iloilo has been a staunch supporter of Frank Bainimarama
Fijian President Ratu Josefa Iloilo has announced that he has taken over the country's government.
It comes a day after a court ruled that the current military leadership was illegally appointed after a 2006 coup.
In a nationally televised address, the president said he had annulled the constitution, assumed all governing power and sacked the country's judges.
He spoke after meeting Commodore Frank Bainimarama, the army chief who toppled the civilian government in the coup.
"I hereby confirm I have abrogated the 1997 constitution and appointed myself as head of state in the new order," Mr Iloilo said.
Mr Iloilo said he would appoint an interim prime minister for five years to allow time for necessary reforms before elections could be held.
"You cannot have a country without a government. The machinery of government must continue," he said.
He also said the country would hold elections in 2014 - much later than the deadline of this year set by the constitution Mr Iloilo has just annulled.
The elderly leader's motives in this extraordinary move are unclear, says the BBC's Phil Mercer in Sydney.
Mr Iloilo has been a staunch supporter of Mr Bainimarama, who has repeatedly ignored international demands to restore democracy, our correspondent says.
Frank Bainimarama resigned as interim PM after the court ruling
The president's actions could be an attempt to cleanse a troubled political system, our correspondent adds, or they could simply be a way for him to reinstate the military administration under a revised constitution.
Observers warned that the interim government could be led again by Mr Bainimarama.
"It looks like a prepared statement by Bainimarama, delivered by Iloilo," Rod Alley, a senior fellow at New Zealand's Centre for Strategic Studies, told the Associated Press news agency.
"This is extraordinary and doesn't look good for Fiji," he said.
On Thursday, a three-judge Court of Appeal panel upheld a challenge to Mr Bainimarama's rule by ousted Prime Minister Laisenia Qarase.
The court said the military government - the product of the country's fourth coup in 20 years - was illegal and should be replaced with an interim government, led by neither Mr Qarase nor Mr Bainimarama.
Australia and New Zealand have led international pressure on Mr Bainimarama to hold elections this year under the constitution that was in place until now.
US Secretary of State Hillary Clinton this week backed that view.
United Nations Secretary General Ban Ki-moon appealed for calm following Thursday's ruling.