Britons ignoring pleas to leave 'have not grasped danger of war'

British officials are concerned that too many Britons are ignoring advice to leave India, despite the danger of a war with Pakistan that could turn into the world's first nuclear exchange.

Gerry McCrudden, first secretary at the British High Commission in Delhi said yesterday: "We are concerned that, while people are leaving, they are not heeding the travel advice and leaving in the numbers we would like."

Last Friday, Jack Straw, the Foreign Secretary, said his "clear duty of care" for the safety of UK citizens in the region had made him decide "to amend our travel advice to India. This now advises, for the time being, against travel to India. British nationals there should consider leaving."

Several other countries have issued similar warnings, including the United States, France, Germany and Australia.

The publication of the advice coincided with a small but noticeable reduction in war hysteria in both Delhi and Islamabad. As a result, a mood of incipient panic at the weekend has subsided and, although expatriates continue to leave, there are still empty seats on planes heading west.

Mr McCrudden said: "People don't believe it is as big a danger as we say it is. They have not grasped the extent of the risks." The new advice was not, he emphasised, a way of increasing diplomatic pressure on India and Pakistan, but was based on a sober assessment of the risks.

"We are in a pretty unique situation here," he said, "thinking about the safety of our staff and UK citizens in the shadow of a possible nuclear conflict. There are between 50,000 and 70,000 British subjects in India at any one time, including about 10,000 on holiday." The logistical problems in helping such numbers in the event of war were obvious, he said.

There have been small but hopeful developments during the past few days. The US is said to be satisfied that Pakistan's President, General Pervez Musharraf, has ordered an end to the infiltration of Islamic radicals across the Line of Control into Indian-controlled Kashmir. But a security analyst pointed out that such improvements may not be enough to avert a war.

With a million troops strung out along the borderthe risks of the situation worsening were considerable. "The risk of nuclear war is fairly low, but not non-existent," the analyst warned. He said he believed there were two possible ways Pakistan might use its nuclear weapons. "One would be firing a warning shot with one nuclear device. The other would be to use all its nuclear weapons at once, for fear of their being destroyed by an Indian counter-attack." Pakistan is believed to possess between 25 and 50 nuclear weapons.

He pointed out that if a war started and escalated rapidly, the first thing to happen would be that Indian air space could be closed to civil aviation – leaving thousands of British citizens stranded in the teeming, flat expanses of the North Indian Plain.

A steady stream of expatriates is already leaving India, with several missions, including the United Nations and even the Red Cross cutting their staff to a skeleton presence. Only some 6,000 British citizens are registered with the Delhi High Commission. Some 30,000 to 40,000 of the British nationals in India are said to be of Indian origin, most of them British Overseas Citizens who do not have the right of abode in the UK. But Mr McCrudden said yesterday that Britain has a duty to give consular protection to all its citizens.

British Overseas Citizens are entitled to stay in Britain for up to six months.