The statement came after the navy accused the separatist rebels of starting the clash Thursday that has fanned fears about the future of an already fragile ceasefire on the island torn by ethnic conflict.

The rebel Liberation Tigers of Tamil Eelam (LTTE) told Scandinavian truce monitors that their boats were attacked first by the Sri Lankan navy off the island's northwestern coast of Mannar.

"When three of our boats were travelling in the Mannar seas, the Sri Lankan navy intercepted the fleet and started firing," LTTE's political wing leader S. P. Thamilselvan said in a letter to truce monitoring chief Hagrup Haukland.

"Our members had to return fire for self-protection."

Thamilselvan said the navy retreated, leaving one of their patrol boats behind.

The Tigers noticed three sailors aboard the abandoned craft and said two of them were already dead. The wounded survivor was rescued, but later drowned when the rebel boat to which he was taken sank after taking on water, he said.

He said the LTTE had repeatedly asked the Scandinavian truce monitors, known as the Sri Lankan Monitoring Mission, to make arrangements for Tigers to travel by land and sea in accordance with an understanding reached earlier.

"Please be advised that our members would continue this practice of travelling in the seas with arms for self-defence and it is essential that our request be officially responded to to formalise travel in the future.

"Early action ... would avoid recurrence of such incidents," he told the

The Sri Lankan navy accused the Tigers on Thursday of abducting three sailors after the gunbattle and said it believed the men had been killed.

The incident marked a worsening of clashes between rebels and government forces despite diplomatic moves to arrange direct talks between the parties to stop the island sliding back into war.

Government spokesman Nimal Siripala de Silva said Colombo had lodged a complaint with the Scandinavian truce monitoring mission.

"We are asking the international community to take note of this gross violation of the ceasefire and apply pressure on the Tigers to halt this cycle of violence," de Silva said on Thursday.

Forty-two people have been killed this month alone in violence linked to the ethnic conflict, heightening fears about the fate of the ceasefire that has been in force since February 2002.

Police said they expect a further escalation of violence in the troubled region as peacebroker Norway tries to arrange talks to salvage the truce.

President Mahinda Rajapakse reiterated an offer Wednesday to hold talks with the Tigers anywhere in Asia, saying he was "ready for talks as soon as the Tigers are ready."

Japan has offered to host the talks. But the Tigers are insisting they be held in Oslo, a demand rejected by Colombo.

This week Sri Lanka's key financial backers -- the United States, the European Union, Japan and Norway -- urged the Tigers to end the latest cycle of violence.

The quartet has promised billions of dollars to rebuild the country's war-shattered economy if the two sides show progress in ending three decades of bloodshed that has claimed over 60,000 lives.

Thursday's naval battle is the latest in a series of such clashes since the truce began.

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