That offer, though, was quickly withdrawn the moment it became clear that many of those responsible for the attacks were of Pakistani origin and had been trained at camps with long-standing links to the ISI.

Now, just as the world's media turn their attention elsewhere, tensions between the two nuclear-armed powers are once more reaching a critical stage. The Pakistani government has substantially raised the stakes by declaring that it is ready to go to war if India persists with its allegations that senior officials within the Pakistani security establishment had, at the very least, advance knowledge of the attacks.

At the heart of the crisis lies the murky, but undeniable, relationship between the ISI and Lashkar-e-Taiba (LeT), the Kashmir-based terrorist group widely held to be responsible for the Bombay attacks. LeT was set up in the late 1980s to fight alongside the Taliban in its campaign to drive the Russians out of Afghanistan. It later received instruction and funding from the ISI, in return for attacking Hindus in the Indian-controlled states of Kashmir and Jammu, as part of the Pakistan's attempts to "liberate" Muslim-dominated Kashmir from Delhi.

In addition, LeT receives funding from Saudi Arabia's fundamentalist Wahhabi sect, which has encouraged the group to adopt an ideology that ranges far beyond simply challenging India's sovereignty over Kashmir. A recent pamphlet issued by LeT decrees that India is an existential enemy of Islam, just like America and Israel, and that a campaign of jihad should therefore be waged until Islamic rule has been restored to all parts of India.

The anti-Western and anti-Israeli sentiments expressed in the organisation's recent literature would explain the group's decision to target high-profile Western hotels, such as the Oberoi, and one of Bombay's leading Jewish centres, where six Israelis were murdered. It has also prompted speculation that LeT has established links with al-Qaeda.

The sophistication shown by the Bombay terrorist cell prompted Admiral Mike Mullen, chairman of the US joint chiefs of staff, to concede yesterday that Pakistan-based terror groups have developed the ability to operate at a "much higher level".

Last week a congressional report concluded that it was "highly likely" that the American mainland would suffer some form of chemical, biological or nuclear attack at the hands of Islamist terror groups within the next four years. And if groups such as these have the capability to attack America, they certainly have the ability to penetrate countries such as Britain, which are far closer to the major training camps in Pakistan. Britain's security authorities are taking no chances – this week, they intensified river patrols on the Thames as a precaution against a Bombay-style attack.

Britain and America are rightly concerned about the growing sophistication and radicalisation of Pakistan-based terror groups. It is hardly surprising, then, that the Indian authorities are rapidly losing patience with what they regard as Islamabad's stalling tactics. It's not just that the Indians believe they have uncovered clear proof that the Bombay terrorists, however much they tried to conceal their identities, originated from Pakistan and were, in all probability, trained in camps run by the ISI. It is the growing realisation that the attacks were not motivated by the age-old dispute over Kashmir, but by the terrorists' desire to undermine the very foundations of the Indian government.

So long as the Pakistani government declines to take effective action to stop LeT carrying out repeat attacks in Indian territory, Mr Singh's government is going to come under intense domestic pressure to take matters into its own hands. And if that happens, we will have a lot more to worry about than the conflicts in Iraq and Afghanistan. Telegraph