The deal, which lifts sanctions on the export of civilian nuclear fuel and technology to India, was approved by the US Congress on December 9 and was to be signed into law by US President George W. Bush Monday.

Top Indian nuclear scientists and the main opposition Bharatiya Janata Party (BJP) have criticised the deal, which places a moratorium on nuclear testing by India.

The government's communist allies also say the agreement will allow US interference in the country's foreign policy.

"India cannot become a client state of the United States," top BJP member L.K Advani said, calling for a rejection of the agreement, first reached between Singh and Bush in July 2005.

"Most of those who voted for or against the bill (in the US Congress) were concerned with whether the bill imposed curbs on our weapons capabilities and if it did they voted for it," Advani said.

But Singh insisted there would be no global scrutiny of India's strategic programme.

"Our strategic programme will respond to our own decisions and not be subjected to any international scrutiny," Singh told parliament.

Singh said that the accord had ended India's status as a nuclear pariah since it first conducted a nuclear test in 1974, inviting international sanctions.

Under the deal, India -- a non-signatory to the nuclear Non-Proliferation Treaty (NPT) -- agreed to place its civilian-use nuclear reactors under scrutiny.

The agreement includes a set of international safeguards to be approved by the International Atomic Energy Agency (IAEA), the global nuclear watchdog, to which India must adhere.

The law also asks for India's participation in US efforts to "dissuade, isolate, and, if necessary, sanction and contain Iran" -- a clause for which the government has come under fire.

Singh told the legislature that the final agreement contained elements which "continue to cause concern", but that the US administration had assured India that it would comply with its commitments made in July.

"We will seek full civil nuclear cooperation on the terms acceptable to us," Singh said, adding that New Delhi will press Washington for clarifications during talks.

Experts said there were still significant hurdles to be crossed in tough negotiations on the agreement.

"There are still many steps before it becomes something that is complete," Michael Levi, a science and technology expert at the Council on Foreign Relations, a respected US think tank, told AFP.

They include devising a bilateral agreement incorporating all technical details of the deal, as well as nuclear safeguards for India that must be endorsed by the international community.

The bilateral agreement will have to be approved again by the US Congress, to be controlled next year by Democrats known for their strong non-proliferation views.

All rights reserved. © 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.