In Washington, White House spokesman Mike McCurry said president Bill Clinton was "very disappointed" by Sharif's action. A set of sanctions against Pakistan was being prepared that would be announced by Clinton later. White House officials said the sanctions would include cut-off of most US aid to Pakistan and a suspension of Washington's backing for international lending to Islamabad.

Japan, Pakistan's biggest aid donor and trading partner, would also consider slapping tough economic sanctions, Japanese government sources said. The impact of the possible sanctions was assessed at around $2 billion by a source in Jardine Fleming in Pakistan.

The news of Pakistani blasts touched off a flurry of activity in New Delhi with prime minister Atal Behari Vajpayee intervening inthe ongoing debate in the Lok Sabha to announce that these tests only vindicated the country's nuclear policy.

The house was debating the nuclear tests conducted recently by India at Pokharan.

Making a brief intervention, Vajpayee said the government had received reports about Pakistan's nuclear tests. "If this is true, then it vindicates our nuclear policy", he said.

The house plunged into an uproar as soon as former external affairs minister K Natwar Singh informed the speaker about the Pakistani tests. Members cutting across party lines insisted on getting more details. Information and broadcasting minister Sushma Swaraj suggested that the house be adjourned till the details were available. Parliamentary affairs minister Madan Lal Khurana agreed to debate the issue soon after the presentation of railway budget on Friday, suspending the customary private members' business.

External affairs ministry officials made no bone of the fact that Islamabad had merely tried to cook up an imaginary theory tojustify the three nuclear tests they carried out later in the day.

Describing the allegation as utterly absurd, an external ministry official spokesman said India stood committed to uphold the bilateral agreement on prohibition of attack against nuclear installations and their facilities.

According to reports reaching here, the US had no immediate reaction. The reports suggested that US president Bill Clinton would be talking to Pakistani prime minister Nawaz Sharif to get the details. American defence secretary William Cohen was, however, quoted just before the blasts as saying that Pakistan would have to suffer sanctions if it went ahead with the tests as per US laws.

A studied Chinese reaction was awaited on the issue even though reports reaching from Beijing said China had advised Pakistan to make "a comprehensive assessment of the situation arising out of India's nuclear tests".

That Pakistan had been preparing for the tests immediately after India's successful blasts was amply clear to theinternational community which tried its best to dissuade it to go ahead with the tests. The US had specially sent a mission to Islamabad for the purpose. All this, however, fell on deaf ears of Pakistan.

Unlike India's tests, the preparations of the Pakistani nuclear tests were widely known. Most morning papers of Pakistan on Thursday gave a clear hint of these tests, reports confirmed.Rupee dips

The rupee came perilously close to touch the 42-level on the kerb against the dollar on Thursday. The rupee sank to 41.90 as panic gripped the market on the news of Pakistan's series of nuclear tests.

Kerb upbeat

The news of the Pakistani nuclear tests saw the local punters quickly cover up their positions. Although the mood at the kerb market was upbeat, it failed to reflect on the stock prices which was traded on a steady note.