Sri Lanka's Tamil Tiger rebels declared a unilateral ceasefire on Sunday, with the military having surrounded them in a tiny area along with thousands of civilians, but the move was immediately rejected by the government.
"In the face of an unprecedented humanitarian crisis and in response to the calls made by the U.N., EU, the governments of India and others, the Liberation Tigers of Tamil Eelam (LTTE) has announced a unilateral ceasefire," an LTTE statement said.
Sri Lanka responded by saying the rebels must either surrender or be destroyed.
"That is a joke. They were not fighting with us, they were running from us. There is no need of a ceasefire. They must surrender. That is it," Defense Secretary Gotabaya Rajapaksa told Reuters in a telephone interview.
The top U.N. humanitarian official John Holmes arrived in Sri Lanka on Saturday amid mounting pressure on the LTTE to surrender, and the government to halt its offensive to wipe out a foe it has fought since 1983.
Tens of thousands of civilians remain trapped in a tiny strip of coastline studded with coconut groves, a former army-declared no-fire zone that has become the final conventional battleground in Asia's longest-running war.
International concern is mounting about the welfare of the those held by the LTTE in fighting, and more than 100,000 who fled en masse after troops blasted an earthen barricade on Monday.
Internal United Nations tallies say nearly 6,500 have been killed in fighting since the end of January.
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