COLOMBO: Sri Lanka's President has ordered government troops to halt their offensive against cornered Tamil rebels for two days to give tens of thousands of civilians a chance to escape the fighting.

The brief pause in hostilities follows increasingly urgent international calls for civilians to be protected as the military attempts to finally crush the separatist Tamil Tiger guerillas. The United Nations estimates 100,000 civilians are trapped in a "no-fire zone", the last remaining territory held by the rebels, who have been pushed close to defeat.

The President, Mahinda Rajapakse, said the ceasefire would allow civilians to leave the conflict zone and to celebrate the Sinhala and Tamil new year in the next two days. "[Mr Rajapakse] has directed the armed forces of the state to restrict their operations during the new year to those of a defensive nature," his office said.

It said the halt would enable Tamils to "celebrate these festivities in a suitable atmosphere and to have uninhibited freedom of movement from the no-fire zone".

The Tigers, who are accused of holding the civilians hostage, have suffered months of battlefield setbacks that could finally end their campaign for an independent Tamil homeland after 37 years of violence.

Mr Rajapakse reiterated the Government's demands that the Tigers lay down their arms and surrender to security forces who have forced them into a strip of coastal jungle in the island's north-east. The United Nations Secretary-General, Ban Ki-moon, welcomed the respite as a "useful first step" and said more aid would be sent to help civilians. He called on the Tigers to "take concrete and immediate steps to protect civilians by respecting the pause for its full duration".

Britain, the former colonial power in Sri Lanka, also praised the government ceasefire. Urging the Tigers to follow suit, it said it was vital that civilians were able to move freely out of the conflict area.

There was no immediate comment from the Tigers, but the pro-rebel Tamilnet website said the military had fired 300 shells into the "no-fire zone" in 45 minutes early on Sunday.

"Heavy civilian casualties are feared," it said, adding that at least two people had died.

Agence France-Presse