The deal, which aims to give India access to US civilian nuclear technology for the first time in three decades, had been expected to be approved by the US Senate last week before it adjourned for elections in November.

However, the chamber could not take up the bill due to differences between Republicans and Democrats despite both sides expressing strong support for the deal and pointing fingers at the other for the delay.

"The bill actually enjoys bipartisan support and it is our hope that this will find its way through US domestic legal procedures as soon as possible," said India's new foreign secretary, Shiv Shankar Menon.

"I think our interest in the agreement, in it passing through Congress and our interest in the terms staying as they are, is quite clear," Menon told reporters after taking office.

Privately, some senior Indian officials expressed helplessness about a deal that has faced a storm of opposition in both countries since it was agreed in principle by President George W Bush and Prime Minister Manmohan Singh in July 2005.

The Senate could take up the bill when it returns for a "lame duck" session after the November elections, but other approvals are needed beyond that and they are likely to push the deal's final fate into 2007.