A discussion on the India-United States civil nuclear deal will take place in the Rajya Sabha on Tuesday amid renewed pressures from the Left parties over the agreement and opposition demand that Prime Minister Manmohan Singh [Images] should reply.

Ahead of discussion, the Communist Party of India-Marxist stepped up the attack on the deal, alleging that its 'larger agenda' was to convert New Delhi into a 'subordinate ally' of Washington.

It is unclear what stand the Samajwadi Party and the Telugu Desam Party take in the house as the two key parties in the third front had either been soft or had stayed away from the discussion in the Lok Sabha.

Parliamentary affairs minister P R Dasmunsi insisted that only external affairs minister Pranab Mukherjee will reply to the debate and remained non-committal on whether the Prime Minister would at least intervene.

The Bharatiya Janata Party said the prime minister should not remain a 'mute spectator' to such an important debate and that it would like to see him reply to the questions raised. But if the government decided to field Pranab Mukherjee, then Dr Singh should intervene during the debate, it said.

Science and technology minister Kapil Sibal, who is a member of the United Progressive Alliance-Left committee on the deal, and Congress spokesman Abhishek Singhvi are expected to intervene.

Asked whether the prime minister would intervene during the debate, Dasmunsi said Dr Singh has already made four or five appearances on the issue and has also made elaborate statements in both houses.

The discussion would be a short one like in the Lok Sabha which does not entail voting.

However, Left sources said that Samajwadi Party is also likely to oppose the deal in the upper house. The All India Anna Dravida Munnetra Kazhagam has already given a notice for a discussion under a rule that entails voting.

Incidentally, a number of senior leaders who have had strong views on the accord, including Brinda Karat and Sitaram Yechury of the CPI-M, Arun Shourie and Yashwant Sinha of BJP, are members of the upper house.

The discussion had taken place in the Lok Sabha on November 28, when the government made it clear that the deal does not bar India from carrying out nuclear tests in future.