WASHINGTON The US Senate on Wednesday endorsed a landmark US-India nuclear agreement, removing the final legislative hurdle for resumption of civilian nuclear trade between the two countries after three decades.

Senators voted 86-13 to give overwhelming approval to the deal and lifted a ban on civilian nuclear trade imposed after India first conducted a nuclear test explosion in 1974.

The agreement, which will help provide critical energy to fuel Indias booming economy, was already approved by the US House of Representatives last weekend.

Solid congressional backing underscored bipartisan support for President George W. Bushs bid to improve relations with India, the worlds most populous democracy, officials said.

“This is one of the most important strategic diplomatic initiatives undertaken in the last decade,” said senior Republican Senator Richard Lugar.

“By concluding this pact, the US has embraced a long-term outlook that will give us new diplomatic options and improve global stability,” he said.

An attempt by several senators earlier to amend the agreement to make it clear that the deal would be scrapped if India carried out further nuclear test explosions was rejected by a unanimous vote.

“If India resumes testing, the 123 agreement is over,” Lugar said, citing US laws and persistent assurances from the State Department.

In a statement, US President Bush said he looks forward to signing the bill into law.

“This legislation will strengthen our global nuclear nonproliferation efforts, protect the environment, create jobs, and assist India in meeting its growing energy needs in a responsible manner,” Bush said.

India, which has not signed the NPT, an international nuclear non-proliferation treaty dating from the 1960s that is intended to prevent the spread of nuclear weapons, has argued that it has the sovereign right to conduct atomic weapon tests.

Bush and Indian Prime Minister Manmohan Singh first agreed to the deal in 2005 but divisions within Indias ruling coalition partners as well from the opposition delayed approvals in New Delhi.

Both the main opposition Hindu nationalist Bharatiya Janata Party and the communists slammed the deal, saying it would curb Indias military options and bring the countrys foreign policy too much under US influence.

The deal offers India access to sophisticated US technology and cheap atomic energy in return for New Delhi allowing UN inspections of some of its civilian nuclear facilities.

Military nuclear installations will not be opened for scrutiny.

With US-led diplomacy, the deal had already won approvals from the International Atomic Energy Agency (IAEA), the UN nuclear watchdog, and the Nuclear Suppliers Group (NSG), which controls global atomic trade.

Following the NSG greenlight, India signed a landmark atomic energy pact with France earlier this week.

Critics say the deal does grave damage to global efforts to contain the spread of nuclear weapons, by letting India import nuclear fuel and technology even though it has tested nuclear weapons and never signed the Non-Proliferation Treaty (NPT).

“The U.S.-Indian Agreement for Nuclear Cooperation is, nonetheless, a nonproliferation disaster,” said Daryl Kimball, head of the Arms Control Association.

“Contrary to the counterfactual claims of proponents and apologists, it does not bring India into the nonproliferation mainstream,” Kimball continued.

“India gets to have their cake and eat it too,” Democratic Senator Jeff Bingaman agreed.

“The agreement also makes it difficult for us to justify to other NPT signatories such as South Africa, Taiwan and Brazil which have postponed their own nuclear weapons programs as part of signing up for the NPT,” Bingaman said