NEW DELHI, Feb 6: A senior aide to former US president Bill Clinton says that his administration was seriously worried by the prospect of the Kargil standoff between India and Pakistan turning into a nuclear war , the Indian Express reported on Friday.

It quoted former US deputy secretary of state Strobe Talbott as saying in an interview that intense personal lobbying by then president Clinton with Nawaz Sharif and Atal Behari Vajpayee, the rival prime ministers during the 1999 crisis, had helped de-escalate tensions.

In a separate TV interview quoted by the Express, Mr Talbott claimed that president Clinton had successfully persuaded the Indian prime minister in 1995, P.V. Narasimha Rao, not to carry out the nuclear tests he was preparing for.

Washington felt that Pakistan, "by precipitating the Kargil crisis, (was) potentially blundering into a nuclear war on the sub-continent," Mr Talbott said. "And this was why then president Bill Clinton refused to give in when Nawaz Sharif wanted...to be paid...wanted a concession of some kind from the Indian side (on Kashmir) and from the American side for pulling back," Mr Talbott said in the interview he gave in New Delhi on Thursday.

The crisis helped bring India and the United States close. "I would argue that the breakthrough moment was in July 1999 when Prime Minister Vajpayee had enough confidence in Clinton and his goodwill that he suspended partially his scepticism about American mediating, or what we called at the time, facilitating, to let Clinton work on Nawaz Sharif in Blair House, and get Nawaz Sharif on an unconditional basis to pull Pakistani troops back on the northern side of the Line of Control," Mr Talbott said.

He said Mr Vajpayee did not request president Clinton to meet Mr Sharif. "What happened was that Nawaz Sharif knew he was in a perilous situation and he called Clinton and said, I'm coming. And Clinton said, don't come unless you're prepared to unconditionally withdraw. Nawaz Sharif said, I'm coming. Clinton repeated it. Nawaz Sharif said, I'm getting on the aeroplane, now.

"So not only did Clinton not have a request from Vajpayee, Nawaz Sharif didn't have a request from Clinton. This was very much at Nawaz Sharif's initiative.

"Clinton decided to let him come. But he also decided that he would have to find a way of staying in the closest possible contact with Vajpayee, throughout the day, that Sunday. And I forget how many times he called, three times or something like that.

"We would take breaks with the Pakistanis. We'd go into the other room, we'd get onto the phone, ten-and-a-half hours difference or whatever, it was already quite late at night.

"And Clinton would simply walk through everything Nawaz Sharif had said, everything that he, Clinton, had said, everything that he, Clinton, intended to do. He was telling Vajpayee exactly what was going on with Nawaz Sharif, sometimes within ten minutes of having finished talking to Sharif.

"President Clinton got himself involved in negotiations because the stakes were truly high.

"We honestly felt that this was the stuff of which nuclear war is made.

"Clinton saw Pakistan, by precipitating the Kargil crisis, as potentially blundering into a nuclear war on the sub-continent. And he felt he should do everything in his power to stop that. "And what Clinton did throughout all of this, was to hold the line. What Nawaz Sharif wanted was to be paid, he wanted a concession of some kind from the Indian side and from the American side for pulling back. He wanted either a promise that the US would mediate, a promise on India's part that it would negotiate the status of Kashmir. And Clinton kept saying, no, no, no."

Mr Talbott said India did not carry out the nuclear tests it was preparing for in December 1995 after the "US found out and President Clinton called up urging him (Mr Rao) not to do so.

There was no formal promise by Mr Rao that India would not test, but "America's message was received and the test didn't happen," Mr Talbott said. "It wasn't a threat but there was a strong argument because it would be contrary to everybody's interest."