The pact, which is the centrepiece of energy-starved India's new ties with Washington after decades of frosty Cold War relations, will give the nation access to long-denied Western civilian nuclear energy technology.

"The two sides are continuing discussions with a view to finalising the bilateral cooperation agreement in civil nuclear energy," Foreign Minister Pranab Mukherjee told parliament, according to a Press Trust of India report.

US Under Secretary of State for Political Affairs Nicholas Burns is expected in New Delhi next week for talks with Foreign Secretary Shivshankar Menon to finalise an agreement to enable the deal to be put into operation.

India agreed as part of the deal to separate its civilian and military nuclear facilities and to allow the civilian sites to be inspected.

Mukherjee denied reports that the agreement was in danger because of differences on various aspects of the pact.

"It's not true," he said.

But differences do remain to be addressed, including over a clause that says the US would cease fuel supplies if India breaches its unilateral moratorium on nuclear testing.