There was anxiety in India whether the deal, which has cleared all international hurdles such as the International Atomic Energy Agency and the Nuclear Suppliers Group, would be able to pass muster in U.S. Congress before it adjourns.

Adding to the anxiety was the fact Congress currently has the bigger headache of approving the $700-billion financial bailout package.

Singh will first attend the U.N. General Assembly session before traveling to Washington, with only five working days left before Congress adjourns.

The nuclear deal will be high on the agenda of Singh's 10-day trip to both the United States and France, another likely nuclear supplier to India, the Press Trusts of India reported.

Before leaving New Delhi, Singh said he looked forward to his meeting with U.S. President George Bush to discuss "the entire range of issues on our bilateral agenda with the United States, including our civil nuclear initiative," the report said.

The Times of India reported there were indications Congress may extend its current session until Oct. 3 to deal with the nuclear deal.

Once the deal becomes law, it will end India's 30-year nuclear isolation and allow it commence nuclear commerce with various suppliers.