VIENNA (AFP) - The United States, following weeks of tough negotiations, finally secured the approval of nuclear supplier nations Saturday for proposals to lift a 34-year-old embargo on nuclear trade with India. The US described the breakthrough - on the third consecutive day of crunch talks - as a "historic" and "landmark" deal that would boost nuclear non-proliferation, while at the same time enabling India to meet its huge energy needs with low-polluting energy. India, for its part, described the deal as an "important step" in the normalisation of its relations with the rest of the world and would help meet the challenge of climate change and sustainable development. The so-called Nuclear Suppliers Group, which controls the export and sale of nuclear technology, reached consensus on a one-off waiver of its rules for India, which refuses to sign the Non-Proliferation Treaty. "This is a historic moment for the N-Suppliers Group, for India, for US-Indian relations, indeed India's relations with the rest of the world," acting US Undersecretary for Arms Control and International Security, John Rood, told reporters at the end of around 90 minutes of talks on Saturday. "Today at the NSG, we have reached a landmark decision to allow for civil nuclear trade with India," Rood said. "This is an important moment also for the strengthening of the nuclear non-proliferation regime," he added. "This is a critically important moment for meeting the energy needs in India, and indeed dealing with the global need for clean and reliable energy supplies." NSG rules ban nuclear trading with India because it refuses to sign the Non-Proliferation Treaty, having developed atomic bombs in secret and conducted its first nuclear test in 1974. The United States wants a special waiver for India so it can share civilian nuclear technology with New Delhi. The United States argues the deal would bring India into the NPT fold and help combat global warming by allowing it to develop low-polluting nuclear energy. Critics say the deal undermines international non-proliferation efforts and accuse the nuclear powers of pursuing commercial and political gains. Indian Foreign Secretary Shivshankar Menon told reporters: "India welcomes the decision by the NSG to adjust its guidelines to enable full civil nuclear cooperation of its members with India." It was the second time in two weeks that the NSG had met to try and agree on a change in its rules and was characterised by hard-nosed bargaining on both sides. Three countries in particular " Austria, Ireland and New Zealand " had been holding out for a clear-cut commitment on India's part to refrain from nuclear weapons testing. And after 17 hours of talks on Friday, a compromise was reached Saturday that was acceptable for the three hardliners. The crunch issue was nuclear testing, since New Delhi has not signed the Comprehensive Test Ban Treaty and India's previous statement that it "remains committed to a voluntary, unilateral moratorium" was not seen as sufficient. Austria said it lifted its objections only after India made a "formal declaration" to stand by its non-proliferation commitments and uphold its moratorium on nuclear bomb tests. Washington was keen to get a deal through so that the US Congress could ratify it before it adjourned at the end of September for November elections. Meanwhile, US President George W Bush and Indian Prime Minister Manmohan Singh Saturday welcomed the "historic achievement" of approval of the deal between the two countries, the White House said on Saturday. "The two leaders congratulated each other on the consensus reached at the Nuclear Suppliers Group meeting in Vienna and expressed appreciation for the joint efforts made there to move forward with civil nuclear cooperation between the United States and India," spokesman Gordon Johndroe said of a phone call between Bush and Singh. Britain also welcomed Saturday the deal, saying it will make a "significant contribution" to global energy and climate security. "It is very welcome that the Nuclear Suppliers Group (NSG) has reached agreement on civil nuclear co-operation with India," said Foreign Secretary David Miliband in a statement.