Washington also feels that the ideas put forth by India on separation of its civilian and military nuclear establishments had not met the "test of credibility" and the negotiations process need to be completed before President George W Bush's [Images] visit to New Delhi in March failing which the "historic opportunity" would be "much less practical".

"We have made it known to them (India) that we would very much like India's support because India has arrived on the world stage and is a very very important player in the world," US Ambassador to India David C Mulford told PTI in a wide-ranging interview in New Delhi.

"If it (India) opposes Iran having nuclear weapons, we think they should record it in the vote," he said. Mulford's observations come amid intensified efforts by the US and the EU-3 (Britain, France [Images] and Germany [Images]) to seek world support for the resolution to be placed at the February two of the IAEA meeting for referring Iran's nuclear issue to the UN Security Council for action.

The US envoy said an "observation" had also been conveyed to India that if New Delhi decides not to vote for the resolution, "...the effect on members of the US Congress with regard to (Indo-US) civil nuclear initiative will be devastating.

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"I think the Congress will simply stop considering the matter. I think the initiative will die in the Congress not because the administration would want it..." Mulford said, five days after Foreign Secretary Shyam Saran held talks with US Under Secretary of State Nicholas Burns on the subject.

The Ambassador said this should be part of the calculations "India will have to keep in mind" while taking a decision on the Iran issue at the IAEA meet. India had voted in favour of the IAEA resolution against Iran in September based on its judgement of its own national interests, he said.

Indo-US N-deal will bring enormous benefits: Kerry

"Again, India will have to make a determination on what its national interests are. That is an issue firmly in the hands of the Indian government to decide," he said. Besides the US Congress, Mulford said India's decision would also have to satisfy the 35-country Nuclear Suppliers Group, in which a consensus has to be evolved with regard to the India-US civilian nuclear cooperation deal, reached between Prime Minister Manmohan Singh [Images] and the US President in Washington on July 18 2006.

Under the deal, to be ratified by the US Congress, Washington will lift sanctions on dual-use technology trade with India for which New Delhi will have to separate its civilian and military nuclear establishments.

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"It is not just the United States. The NSG, which says, wait a minute, if we are going to make this very special one-time change, unique change for India in the nuclear field and they don't stand up on this issue, why should we make the change," he said.