Prime Minister Manmohan Singh (search) proclaimed India "a responsible nuclear power" Tuesday, going before Congress to hail newfound cooperation with the United States on that sensitive issue and an array of tough problems including terrorism and AIDS.

Basking in the glory of President Bush's pledge to seek changes in U.S. laws barring assistance to India's nuclear program, Singh assured members of the House and Senate that his country has "never been, and never will be a source of proliferation of sensitive technologies."

He told a joint meeting of Congress that India (search) "is fully conscious of the immense responsibilities that come with the possession of advanced technologies, both civilian and strategic" and said his country is "a responsible nuclear power."

In only the eighth such appearance by a foreign visitor in the House chamber in the last five years, Singh told lawmakers that the objective of his trip here was "to lay the basis for transformed ties between our two great countries."

Relations between the world's oldest and largest democracies have often been shadowed by suspicion, but have improved markedly in recent years.

Singh, standing before Vice President Dick Cheney and House Speaker Dennis Hastert, said the two countries have common interests in such areas as the fight against terrorism, joint work to combat AIDS (search) and dual efforts to promote democracy — as well as cooperation in developing new energy resources, including nuclear power.

"The field of civil nuclear energy is a vital area for cooperation between our two countries," Singh said.

He noted one area where the two countries do not agree: U.S. resistance to India gaining a permanent seat on the U.N. Security Council (search).

"The voice of the world's largest democracy surely cannot be left unheard on the Security Council when the United Nations is being restructured," he said.

Singh's speech was the first by an Indian leader since former Prime Minister Atal Bihari Vajpayee in 2000. Such occasions are typically reserved for the United States' closest allies.

"The relationship between our two nations has never been stronger," Bush told Singh on Monday during an elaborate White House welcome, complete with a fife-and-drum corps in full Revolutionary-era regalia.

During an Oval Office meeting, the two leaders broke new ground on nuclear power, with Bush offering U.S. help in India's civilian nuclear program despite its military nuclear capabilities and its refusal to sign the Nuclear Nonproliferation Treaty (search). India remains one of only four states that have not signed the treaty.

According to a joint statement issued after their meeting, Bush "stated that as a responsible state with advanced nuclear technology, India should acquire the same benefits and advantages as other such states."

India exploded its first nuclear device in 1974. Three more blasts in 1998 led to sanctions by the United States, Japan and Germany.

Monday's joint statement committed Bush to work on getting Congress to approve changes in U.S. law that would allow the United States to help with India's civilian power program, including the possibility of supplying fuel for India's nuclear reactors at Tarapur near Bombay.

"Cleaner energy resources, including nuclear power, are vital for the future of both our economies," Bush said.

Later, during a luncheon for Singh and his wife, Gursharan Kaur, Secretary of State Condoleezza Rice said, "We welcome India as a global partner, and we look forward to the continued strengthening of democratic institutions, values and peace because this partnership will prosper and move forward."

Singh was honored Monday night with a grand White House dinner — only the fifth of Bush's presidency and the first since his re-election.

Already, Singh's responses to the Bush administration glad-handing suggest that the feeling is mutual.

"Ladies and gentlemen, the refashioning of this bilateral relationship is not merely a matter of diplomatic process," he said at Rice's luncheon. "What we have embarked upon is, therefore, not just for tomorrow, but I sincerely hope and believe that it is for generations to come."

Still, the U.S.-India friendship clearly has its limits: As expected, Singh failed to win Bush's support for India's bid for a permanent seat on the United Nations Security Council.