India on Friday cautiously welcomed the US Senate's approval to President George W Bush's plan for nuclear cooperation between the two countries that would allow the United States to send nuclear technology and fuel to India.

In a calibrated response to the Senate's approval, Prime Minister Manmohan Singh and UPA chairperson Sonia Gandhi separately told delegates at the HT Leadership Summit that Delhi welcomed the step forward but suggested that it was still too early to celebrate.

"We are still a long way to go before nuclear cooperation between India and United States becomes a living reality," Singh said, noting that there were aspects in the two Bills that were "not identical".

Singh stressed that the final version of the deal should be in line with "mutual commitments" made in last year's agreement, a point that Congress president Sonia Gandhi too had articulated during a Q&A session at the Summit earlier in the day.

Gandhi also drew attention to the US legislative reconciliation process and emphasized that nothing outside the July agreement would be accepted. "We sincerely hope that both Houses, the Senate and House of Representatives will sit down and reconcile. All those areas that are not acceptable to us will be excluded and only then we will welcome the bill happily," she said.

Critics of the deal that is symbolic of strengthening Indo-US ties, particularly the Left, have been critical of provisions that make it mandatory for the US President to annually report to the US Congress that India has not detonated a nuclear device.

Singh noted his "sincere" hope that areas where India had concerns would be taken into account during the reconciliation process that expected to take place in the next few weeks.

The prime minister also spoke about the US President's assurance that Bush would work to ensure that the final version of the legislation was in conformity with the agreement of 18 July 2005 and the separation plan of March 2 this year.

India also needs to arrive at a complementary deal with the International Atomic Energy Agency and get an exemption from the Nuclear Suppliers Group, which takes decisions by consensus. India has not yet convinced all the NSG members but has drawn satisfaction from the support from a significant number of members including major countries like Britain and France. But on Friday, Singh - responding to a question on his reaction to the US deal - focused on the nuclear deal getting through the US legislative process in a form acceptable to Delhi.