The Bush administration has started an aggressive campaign to convince skeptical lawmakers of the merits of a landmark civilian nuclear cooperation agreement with India.

Nicholas Burns, a top State Department official, told an audience Monday at the Heritage Foundation that a "very intensive debate" looms on the accord that he helped to settle last week during Bush's visit to India.

"We're prepared for that debate," Burns said at the conservative think tank. "We will advise the Congress that it is our very clear judgment that this is a good deal for the United States as well as for India."

Burns said Bush, Secretary of State Condoleezza Rice and other officials would spend the coming weeks briefing lawmakers.

On Tuesday, the White House planned to meet with lawmakers to discuss the agreement. Richard Boucher, the newly appointed assistant secretary of state for South and Central Asia, was to discuss the deal Thursday at a Washington think tank.

Burns said that, "on a deal as esoteric, frankly, and as complex as this one, members of the Senate and House are going to want to see the details and a full explanation, and we intend to give them."

Despite GOP control of Congress, lawmakers have shown a growing tendency to break from Bush's leadership as his popularity has declined and congressional elections approach in November.

The administration will be working to win over a Congress that was cautious, at best, in reacting to news that Bush and Indian Prime Minister Manmohan Singh had agreed to a deal.

Some critics worried that it could undermine efforts to stop nuclear proliferation. Lawmakers from both political parties said they would wait for the Bush administration to argue its case before deciding whether to vote for nuclear shipments to India.

Singh assured skeptical Indian lawmakers in New Delhi on Tuesday that the pact covering commercial nuclear power will not limit the scope of India's atomic weapons program. "There will no capping of our strategic program," he said.

To bring the agreement into force, Congress must either change, or approve an exception to, the U.S. law that bans civilian nuclear cooperation with countries that have not submitted to full nuclear inspections.

India, which carried out its first nuclear explosion in 1974, has not signed the international Nuclear Non-Proliferation Treaty. Some fear the Bush plan could allow rogue countries outside the treaty to build nuclear weapons programs with imported civilian technology.

Burns gave a preview of the administration's case for the India deal. He defended it as bringing "India into the nonproliferation mainstream" by increasing international inspections and putting U.N. safeguards on India's civilian nuclear power industry.

India has committed to place 14 of 22 reactors under international safeguards, Burns said, and has pledged to put its future civilian reactors under permanent safeguards.

The agreement, he said, "will allow India for the very first time in the life of its nuclear program ... to be able to submit itself in a transparent way for international inspections. We think this is a major, major gain for the nonproliferation community."