'Tough talk ahead on US nuclear deal'

Manmohan Singh said India would not be bound by "extraneous" conditions attached to the deal when it was passed by the US Congress this month, rejecting efforts to constrain New Delhi's policy toward Iran or its own nuclear weapons program.

"India will find it difficult to and cannot accept any such conditions beyond those already agreed to in the understandings with the United States," he told parliament in a debate.

"Clearly difficult negotiations lie ahead."

President George W Bush is expected to sign the bill into law on Monday, a major step toward allowing New Delhi to buy US nuclear reactors and fuel for the first time in 30 years.

But Congress attached several conditions to the law, which have not gone down well with Singh's communist allies and with the main Hindu-nationalist opposition.

Under the bill, the US president would be required to end the export of nuclear materials if India tests another nuclear device as it did in 1998.

The US president is also required to report to Congress annually on whether India was cooperating with international efforts to restrain Iran's nuclear program.