Both sides in the Sri Lankan conflict have been urged to stop fighting and allow for a "humanitarian pause" as UN officials revised their estimate of civilians trapped in the war zone up to 190,000.
The UN, backed by the US and Britain, blamed Tamil separatists for the plight of civilians caught up in the conflict, with dozens believed killed in recent weeks and many more wounded and without medical treatment.
Speaking in New York on Thursday John Holmes, the UN humanitarian chief, said he was particularly concerned about civilians being prevented from leaving the combat area by the Liberation Tigers of Tamil Eelam (LTTE), also known as the Tamil Tigers.
Speaking after an informal UN Security Council briefing Holmes said he was pressing for urgent humanitarian access to the conflict zone in northern Sri Lanka.
‘Humanitarian pause’
"We suggested the idea of some kind of humanitarian pause to allow that to happen and to allow the civilian population to leave," he said.
"This is an extremely worrying situation and therefore, our first appeal is to the LTTE to let the civilians out in a safe and orderly fashion."
On Thursday Rosemary DiCarlo, the US representative to UN for special political affairs, expressed "real concern" over the increasing death toll and condemned the Tigers’ use of civilians as human shields.
"We call on them to lay down their arms, renounce violence and negotiate with the government."
DiCarlo also criticised the Colombo government for continuing to shell areas heavily populated by civilians in its efforts to end a 25-year civil war by subduing the Tamil Tiger separatists.
‘Very concerned’
"We are very concerned that the government of Sri Lanka continues its shelling in areas where there are large numbers of civilians, very close to hospitals and civilian facilities, we understand quite a number of civilians have perished because of these attacks," she told reporters on Thursday.
"We’ve had promises, but we need to see results."
The Sri Lankan government says troops have confined Tamil separatists to an area of about 21 square kilometres, most of which is a government-declared safe zone, on the island’s northeastern coast near the town of Puthukudirippu.
Hews Palihakkara, Sri Lanka’s ambassador to the UN, said his government shared concerns about the civilians saying that it had declared a 48-hour ceasefire period.
But he said the Tamil Tigers were preventing civilians from leaving.
"If the LTTE is ready to let the civilians go today, I will persuade my government to agree to any modality, you can call it a pause or something else," he said.
LTTE denial
A senior Tamil Tiger commander has denied using civilians as human shields and rejected government claims that they were being kept hostage in the combat zone.
In a statement smuggled out of the county to Al Jazeera, Lieutenant Colonel Ilampirathi in Puthukudirippu said they were not stopping the Tamils from leaving.
"It’s a false allegation by our enemies. Our people are determined and continue to stay here despite the attacks from the enemies," responding to questions posed by Al Jazeera and filmed last month.
"Our people are helping the fighters in everyway possible to fight the Sri Lankan forces. They say they have to fight if they are to survive."
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