The agreement came during an elaborate day of ceremony at the White House to promote strong new ties between the United States and India, a rising economic and military power. A joint statement from Bush and Indian Prime Minister Manmohan Singh said Bush will ask Congress to change U.S. law and will work with allies to adjust international rules to allow nuclear trade with India.

''Cleaner energy resources, including nuclear power, are vital for the future of both our economies,'' Bush said after an Oval Office meeting with Singh.

The United States has been restricting India's development of nuclear technologies for years, based partly on India's testing of nuclear devices in 1998 and its refusal to sign the nuclear nonproliferation treaty.

If the new agreement is approved, U.S. firms could help build reactors and supply nuclear fuel in India, including at two reactors built by the United States at Tarapur. The U.S. still will not recognize India as a nuclear power state as India would have liked, however, because it has not agreed to the treaty.

To obtain U.S. support, India agreed to separate its civilian and military nuclear facilities, keep its nuclear technologies from states that do not have them and allow international oversight of the civilian program.

The joint statement said Bush recognized that ''as a responsible state with advanced nuclear technology, India should acquire the same benefits and advantages as other such states.''

U.S. officials worked around the clock over the weekend with the Indian delegation, including an early Monday-morning meeting between Singh and Secretary of State Condoleezza Rice, to hammer out the details. Singh said the resulting agreement with Bush ''gives me great satisfaction.''

''Both of us recognize that civilian nuclear energy has a greater role in meeting global energy demands,'' he said. ''We in India have an ambitious and attainable national road map in this regard.''

Singh didn't get everything on his wish list. Although he told reporters that he made ''a compelling case'' for India to have permanent membership on the U.N. Security Council, Bush told Singh the United States would not support his bid at this time, according to Nick Burns, undersecretary of state for political affairs.