By C. Bryson Hull and Ranga Sirilal
COLOMBO (Reuters) - Sri Lankan troops on Saturday seized the entire coastline for the first time in its 25-year war with the Tamil Tigers, the military said, cutting off escape for separatist rebels now facing total destruction.
Two divisions marching from north and south sealed the coast, while a third completed the encirclement of the Tigers and their leaders, now trapped in barely a square kilometre (.5 sq mile) and without their umbilical access to the sea.
Sri Lanka's military on Friday said it expected to take no more than 48 hours to free tens of thousands of civilians that the United States and United Nations say the Tigers are holding as human shields.
The final push to wipe out the Liberation Tigers of Tamil Eelam (LTTE) came as U.N. Secretary-General Ban Ki-moon's chief of staff, Vijay Nambiar, was due to land in Colombo for the second time in a month to push for a negotiated end to the war.
Nambiar's visit and strong words from the United Nations, United States and others appeared to have come too late to stop a fight to the finish between foes who have ruled out compromise.
"Now we have linked up on the coastline and the Sea Tigers' activities are no more," military spokesman Brigadier Udaya Nanayakkara said. Troops were still closing in on the rebels.
More civilians were fleeing the battle zone, he said. Nearly 10,000 escaped on Friday, bringing the two-day total to 15,000.
The Tigers this week again refused to surrender and free civilians, while the government rejected calls to pause its assault to protect the people.
That signalled a military finish to a war despite the strong urgings of the U.N. Security Council and U.S. President Barack Obama, both of whom spoke out on the war formally for the first time since it intensified earlier this year.
The LTTE on Saturday warned that a conventional victory would only mean a new phase of conflict, galvanised by the deaths of Tamils, pro-rebel web site www.TamilNet.com quoted the LTTE's diplomatic pointman as saying.
"Colombos approach to finish the war in 48 hours through a carnage and bloodbath of civilians will never resolve a conflict of decades. On the contrary it will only escalate the crisis to unforeseen heights," S. Pathmanathan was quoted as saying.
Pathmanathan for years has been the Tigers' chief weapons procurer and is wanted by Interpol. He is believed by diplomats to be hiding somewhere in southeast Asia, with Malaysia, Thailand or Cambodia being seen as most likely destination.
LTTE founder Vellupillai Prabhakaran began his fight for a separate state for Sri Lanka's minority Tamils in the early 1970s, and it erupted into full-scale civil war in 1983.
Military intelligence indicates that Prabhakaran and other senior Tigers are in the remaining LTTE territory, the military spokesman Nanayakkara said.
Tamils complained of marginalisation at the hands of successive governments led by the Sinhalese majority, which has controlled the levers of powers since Sri Lanka won independence from Britain in 1948.
The war has killed at least 70,000 people since 1983, and United Nations estimates say that nearly 6,500
(Editing by David Fox)