The two rivals have been pressured by the US to ease the tension

US Deputy Secretary of State Richard Armitage is meeting Indian National Security adviser Brajesh Mishra in London, as he begins a tour to promote peace in South Asia.

Mr Armitage's trip coincides with a dramatic thaw in relations between India and Pakistan - the two nuclear rivals in the Indian subcontinent.

On Monday, the Pakistani Government said it would get rid of its nuclear arsenal if India were prepared to do the same.

And last week, the two sides said they would re-establish full diplomatic relations, in what is being seen as a significant first step towards peace.

The BBC's Jon Leyne in Washington says that there has been speculation in South Asia the United States has been behind the recent improvement.

If India is ready to denuclearise, we would be happy to denuclearise - but it will have to be mutual Aziz Ahmed Khan

Our correspondent says that although Mr Armitage - who will visit India, Pakistan and Afghanistan - says he is not bringing a peace plan, Washington has a big interest in improving relations between the two historic enemies, now both American allies.

'Mutual' steps

On Monday, Pakistani Prime Minister Zafarullah Jamali received a major boost after the country's main political parites extended their support to his peace moves.

Mr Jamali had hosted a meeting of the parties which was attended by the Islamic partiess as well as representatives of former premiers Nawaz Sharif and Benazir Bhutto's parties.

Earlier Islamabad indicated that it was ready to begin talks with Delhi to discuss nuclear disarmament.

Conciliatory moves on both sides have earned global praise

"As far as Pakistan is concerned, if India is ready to denuclearise, we would be happy to denuclearise," foreign ministry spokesman Aziz Ahmed Khan said on Monday.

"But it will have to be mutual."

He also said Pakistan had had a "positive response" from Indian Prime Minister Atal Behari Vajpayee after Mr Jamali invited him to Islamabad for talks.

Last Friday, Mr Vajpayee said that careful planning was needed before any meeting took place.

However, Mr Vajpayee said there would be no role for any "third-party" to mediate in the Kashmir dispute, rebuffing a long-standing demand of Pakistan.

The emphasis now seems to be on a more graded and cautious approach, with both Delhi and Islamabad apparently agreeing on initiating official level discussions first, ahead of a possible meeting of the two prime ministers later this year.

The diplomatic moves marked a dramatic change in atmosphere after a long period of heightened tension that saw the US leading outside attempts to prevent war breaking out.

India reacted with fury after armed gunmen attacked the federal parliament in Delhi in December, 2001.

It blamed the attack on Pakistan-based militants it said were supported by the government in Islamabad.

Pakistan denied the accusation.

The ensuing months saw India deploy huge numbers of troops along the common border, with Pakistan responding in kind.