The latest ill-tempered exchanges between Delhi and Islamabad indicate just how bad relations have become between south Asia's long-feuding and now nuclear neighbours.

Pakistan's information minister has said that there was hard evidence that the attack, which killed more than 20 people, was organised by India's intelligence agency.

The mangled wreckage of the train carriage

However, India's foreign ministry dismissed the Pakistani allegations of involvement as totally fictitious and baseless.

A spokesman said the suggestion that India's intelligence agency masterminded the attack was "preposterous".

India and Pakistan have routinely accused each other of responsibility for organising bombings and sponsoring civil unrest in the other country. The allegations are always strongly rebutted.

The accusation and denial will further sour the atmosphere between the two countries.

Inside the carriage, the floor is strewn with wreckage

Both say they want direct talks to try to reduce tension in the aftermath of the two countries' nuclear tests.

The talks would cover not just how to prevent a regional arms race but also the dispute over Kashmir.

But there has been no agreement on dates or on the level of any meeting.

The most likely venue for talks between the two prime ministers appears to be Colombo next month during a summit meeting of the seven south Asian nations.