COLOMBO: Sri Lanka's ex-military chief has said he plans to run for the presidency in January elections in a bid to unseat his former boss Mahinda Rajapakse.

Sarath Fonseka is considered a war hero for having crushed Tamil Tiger rebels who had waged a nearly four-decade armed struggle for an independent homeland.

"I have never lost a battle. I can win this one (the presidency) too," the island's only four-star general told a group of lawyers and journalists late Friday.

"I am definitely coming forward to defeat the president," Fonseka said.

Fonseka, 58, was expected to formally announce his candidacy in presidential elections to be held January 26 at a news conference set for Sunday.

His expected declaration comes after he won the backing of the two main opposition parties earlier in the week.

Rajapakse, 64, called the election two years ahead of schedule in a move aimed at helping the government tap into public goodwill following the end of the country's bloody 37-year separatist conflict in May this year.

Fonseka quit as chief of defence staff earlier in November because of a rift with the president over who should claim credit for the military defeat of the Tigers.

Meanwhile, a group of opposition parties met elections commissioner Dayananda Dissanayake late Friday after he formally announced the date of the presidential poll, an opposition lawmaker told AFP.

"We asked the elections commissioner for international monitors for the elections," the legislature member, who asked to remain anonymous, said Saturday.

The member quoted the commissioner as telling the parties, led by the main opposition United National Party, he "hoped to invite" international monitors from the Commonwealth, the United Nations and Asia.

International monitors have acted as observers in previous elections in Sri Lanka that have been marred by opposition allegations of vote-rigging and intimidation.

The elections commissioner could not be reached for comment Saturday.

Rajapakse narrowly won the 2005 poll for a six-year term with 50.12 percent of the vote by defeating the main opposition candidate Ranil Wickremesinghe.

Wickremesinghe is not contesting the January poll and has backed Fonseka to oust Rajapakse. He accuses the president of granting key state positions to family members and of wanton corruption.

Rajapakse's victory was marred by a boycott of the vote by Tamil Tiger guerrillas who prevented some 350,000 minority ethnic Tamils from voting in the island's north and east.

He is yet to formally announce his candidacy.

Wickramabahu Karunanarathne, the leader of the Left Front, and the leader of United Socialist Party, Sirithunga Jayasuriya are the only candidates to formally announce their bids for the nation's top job.

Sri Lanka, where parliamentary elections are also expected some time before April 2010, has 14 million eligible voters.