India's beleaguered ruling coalition on Tuesday threw its weight behind Prime Minister Manmohan Singh after its vital Left allies refused to budge from their opposition to the India-US nuclear deal.

Ahead of the critical Left-United Progressive Alliance (UPA) nuclear committee meeting on Wednesday, the Congress said it was with Manmohan Singh, who is all for the deal, but it as trying to persuade the Communists to back off.

“We will stand by the prime minister. There is no impasse as consultations are on (with the Left),” said senior party leader Digvijay Singh at the Congress headquarters.

The Samajwadi Party, which has emerged a key player for bailing the UPA out of its crisis of numbers, added to the government's woes by refusing to spell out its present thinking on the deal.

The Forward Bloc, meanwhile, also threatened on Tuesday to withdraw from the UPA-Left Committee on if Wednesday’s meeting does not bear desired results. The party has also called a meeting of its Central Secretariat on July three to "formulate the strategy in the emerging situation."

"We do not want to stretch it too long as there is no point it. Our continuation in the high-powered (UPA-Left) panel depends on the outcome of tomorrow's meeting," Forward Bloc Secretary G Devarajan.

The RSP has already withdrawn its representative from the 15-member nuclear panel and if Forward Bloc follows suit, it could be the second of the four Left parties to do so.

Operationalising the deal

At the heart of the dispute is the Left's insistence that the government should not go to the International Atomic Energy Agency (IAEA) for an India-safeguards agreement, a move it says will operationalise the nuclear deal.

Samajwadi Party chief and former Uttar Pradesh chief minister Mulayam Singh Yadav met Communist Party of India-Marxist (CPI-M) General Secretary Prakash Karat on Tuesday to discuss the nuclear row.

“The United National Progressive Alliance (UNPA) will decide its stand on the deal when it will meet in the first week of July,” Yadav told reporters, referring to the grouping of which his party is a member.

Earlier in the day, Rammohan Rao of the Telugu Desam Party (TDP), another UNPA constituent, also met Karat.

The Congress is wooing the Samajwadi Party to back the UPA government on the deal and on the floor of Lok Sabha. The CPI-M meanwhile announced that its decision-making politburo will meet Sunday to take stock of the latest political situation arising out of the nuclear dispute.

The Left, however, remained unyielding to the entreaties by the UPA allies to stave off a snap general election - which will become a real possibility if the Communists desert the government.

“Let them (government) come out with a new proposal. We will consider it. At no time has the Left pulled down a government. (But the government) should not go ahead,” Communist Party of India (CPI) General Secretary AB Bardhan said.

Poll-jittery UPA allies are desperately trying to bridge the widening gap between the Congress and the Left.

Leaders of UPA constituents - Lalu Prasad of Rashtriya Janata Dal and Ramvilas Paswan of Lok Janshakti Party - have tried to convince the prime minister and Congress President Sonia Gandhi that while they favour the deal, this was not the right time for a general election.

The allies fear that elections at this juncture when inflation has touched a 13-year-high at 11.05 percent will hurt them electorally.

DMK chief and Tamil Nadu Chief Minister M Karunanidhi has told Left leaders that a snap poll will only help the Bharatiya Janata Party (BJP), the UPA's main political adversary. The BJP is itching for an election.

The UPA allies have tried to convince the Left that they will ensure the government does not operationalise the deal provided the Left allowed New Delhi to approach the IAEA to decide India-specific safeguards.

The Left leaders have rejected the argument saying deciding the India-specific safeguards would automatically operationalise the deal.

The CPI-M has warned that it will approach President Pratibha Patil with a letter of withdrawal of support to the government if the IAEA was approached.

Even though there was no thaw in the Cold War, the UPA allies put up a brave face and maintained there was no threat to the government. "There is no imminent threat,” Shipping Minister T.R. Baalu told reporters.

Agriculture Minister and Nationalist Congress Party leader Sharad Pawar, who has been trying to negotiate the deal on the UPA's behalf with the Left, told reporters: “I am not contesting elections. So I am not worried about them.”

The BJP has said that it expected the government to fall by August 15. On Monday, BJP leader and prime ministerial candidate LK Advani said that the UPA government was in ICU (intensive care unit) and would collapse soon.