New Delhi - The Indian parliament is due to hold a vote of confidence Tuesday in the Congress party-led government, which could lead to early polls or scupper a nuclear deal with the US.

The vote was called after the United Progressive Alliance's (UPA) communist partners withdrew their support in protest at the nuclear deal, which they say could impinge on India's sovereignty.

Under the nuclear agreement, the US would provide India fissile material and technology for civilian reactors, ending a three-decade ban. India would in turn open its civilian nuclear reactors to international inspections.

The second day of debate on the confidence motion began amid noisy scenes Tuesday as Finance Minister P Chidambaram taunted left-wing members of parliament.

"There are some people in India who do not want us to catch up with China. There are some people in this country who do not want us to get ahead of China," Chidambaram said, sparking protests from communist MPs known to be ideologically close to China.

Moments before the stormy session began, a confident Prime Minister Manmohan Singh arrived at parliament flashing the V sign for victory.

Singh was scheduled to reply to the debate Tuesday evening, after which the confidence vote is expected to take place.

But even after weeks of horse-trading and defections, the vote is expected to be close.

The government will survive if it obtains 271 votes out of 541 in parliament.

Projections by Indian media said the UPA, whose seats have been reduced to 226 after 59 lawmakers from the left withdrew their support, would garner between 268 and 272 votes with help from the regional Samajwadi Party and other smaller parties.

But the possibility of last-minute defections from the 34-member Samajwadi has created a headache for the UPA.

Congress was also banking on nearly 10 abstentions from the opposition National Democratic Alliance.

A defeat for the UPA would trigger political uncertainty in the face of slower economic growth rate and double-digit inflation. It could also spell the death of the nuclear deal.

The UPA government is scheduled to complete its five-year term in May 2009. (dpa)