Sri Lanka's military said troops seized the entire western coast of the Indian Ocean island on Saturday, capturing the key Pooneryn area where Tamil Tiger rebel artillery had kept soldiers at bay since 1993.

With the military controlling Pooneryn, a strategic spit of land that runs parallel to the neck of the northern Jaffna Peninsula across a narrow lagoon, it will be in a position to strike the rebel capital of Kilinochchi from three sides.

In one of Asia's longest-running insurgencies, at least 70,000 people have been killed in Sri Lanka since 1983.

"We have completely taken over Pooneryn. We have gone up to the town, and control the roads from Pooneryn to Paranthan," military spokesman Brigadier Udaya Nanayakkara said.

The Defence Ministry said troops had encountered stiff resistance as they fought through marshlands south of Pooneryn and across the Paranthan junction overnight.

The Liberation Tigers of Tamil Eelam (LTTE) had no immediate comment.

Previously, the LTTE had used heavy artillery to prevent two army divisions garrisoned on Jaffna, in army hands since 1995, from moving south to Kilinochchi.

"We didn't find any artillery, because they must have taken those pieces away or hidden them," Nanayakkara said. Saturday's capture came after months of heavy fighting on the west coast.-Reuters