But for the moment, India has firmly rejected any suggestion it will intervene.

It is not India's responsibility to evacuate Sri Lankan soldiers

Foreign Minister Jaswant Singh

Earlier, a delegation of Buddhist monks had petitioned India's high commissioner in Colombo.

Sri Lanka's influential Buddhist clergy have historically opposed Indian military intervention, even threatening suicide if Indian troops landed on the island.

Painful memories

India paid a heavy price when its intervention in the 1980s went badly wrong.

In 1971, India helped put down a Marxist rebellion in Sri Lanka.

Bitter history

1971 Troops sent in to quell rebellion 1987 Rajiv Gandhi sends in IPKF More than a 1,000 die 1990 Troops pullout 1991 Rajiv Gandhi assassinated

The next intervention took place in July 1987, when Prime Minister Rajiv Gandhi sent in the Indian Peace Keeping Force (IPKF) to disarm the Tigers.

But they ended up being drawn into the conflict, when the rebels refused to lay down their arms.

More than 1,000 soldiers died and India was forced into an embarrassing withdrawal, after being heavily criticised at home.

Domestic politics

The memory has scarred Indian policy makers who fear a similar outcome if the country is drawn in again.

'No government can forget the Gandhi assassination'

"The spillover was quite serious and even led to the assassination of Rajiv Gandhi," says political analyst Mahesh Rangarajan.

His comments are echoed by former Indian foreign secretary, SK Singh, who said no government could forget the brutal killing in 1991.

The government also has to consider the sentiments of powerful Tamil parties, which make up the governing coalition in Delhi.

"If India does decide to help . . . and if some Tamil civilians are killed after that, those groups will be baying for the government's blood," says Mr Rangarajan.

Vajpayee has an eye on domestic opinion

India is home to over 55 million Tamils, who live in the southern state of Tamil Nadu, separated from Sri Lanka by a narrow strait.

They share strong historical and cultural links with Sri Lanka's Tamil minority and even provided a base for the LTTE for a while.

Regional conflict

At the same time, India cannot afford to stand by idly.

It is conscious of its image as a regional power and is lobbying to become a permanent member of the UN Security Council.

Diplomats and analysts say Delhi realises that if it stays away from the conflict, it could open the door to other countries to step in to what is, effectively, its backyard.

It represents a dilemma for the country's rulers and one that they have to approach with considerable caution.