Indicating that the passage of the bill to facilitate implementation of the Indo-US nuclear deal would not be a smooth affair in Congress, the Bush administration has stated that it was against 'renegotiating' the 'complex' agreement as it would risk never reassembling it again.

However, the administration has said it was open to ideas from lawmakers on ways to strenghten the accord.

Citing India's good track record on non-proliferation, the administration also sought to silence critics of the deal, saying the pact would not enhance New Delhi's nuclear weapons programme or lead to an arms race in the region.

Hours after the administration tabled a bill in Congress seeking to amend the US Atomic Energy Act to facilitate the deal, US Under Secretary for Political Affairs Nicholas Burns noted that the agreement was a break from the 'conventional wisdom of the past'.

Burns said that though Congress members are welcome to put forward their suggestions, the administration would not like to renegotiate the deal.

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"This is a complex agreement. To reopen it, we're probably at risk of never being able to achieve it again and to reassemble it. So what we've said to members of Congress who have raised this with us is that we welcome all ideas. There may be ideas that do not require renegotiation, that may help to reinforce or strengthen this agreement. We're open to all of them. But we wish not to renegotiate", he said.

Burns said, "We have said to members, if you can get us ideas that do not require us to renegotiate the deal, but that might strengthen it by asking to certify certain things that may happen in the future, that would be welcome. And we've already received such ideas."

The administration is keen on Congressional passage of the Bill by April-end, so that Washington could approach the Nuclear Suppliers Group to change its policy on facilitating transfer of nuclear fuel to India, which has not signed the NPT. The 45-nation body, which monitors nuclear transfers, is scheduled to meet in May.

Stressing that India is a trustworthy partner and has a good track record on non-proliferation, he said, "It's interesting that a lot of countries around the world have a lot of experience with India in the nuclear realm. And of course, a lot of countries have taken a close look at India's record on non-proliferation.

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"The consensus that I hear, talking to most of the members of the Nuclear Suppliers Group, is that we all agree on one thing. That India, while it's been outside the NPT, has conformed to a lot of the practices of the countries inside the NPT, which is another anomaly of India's current state," he said.

The senior official said the administration fundamentally disagreed with the argument that the civilian nuclear deal enabled India to enhance its nuclear weapons programme.

"All of us agree that India does have a good record in not proliferating its nuclear technology and nuclear materials. So while people are free to make whatever charges they want, that is the consensus internationally," he said.

Complete coverage: Indo-US nuclear tango