The Left parties may walk out of the coordination committee with the United Progressive Alliance, once again, at the end of this week-end, over the issue of Indo-US civil nuclear deal, said a senior leader of the Congress.

The boycott of the powerful political body by itself will not destabilise the government, but the move has the potential to pave the way for a bigger crisis at short notice.

That emergency can come if and when the government operationalises the Indo-US nuclear deal.

The fast-moving events of the past few days events have made one thing clear: The Left party leaders have reached the limits of their tolerance.

The Indo-US nuclear deal could bring an end to the Left parties' support to the Manmohan Singh-led UPA government if it presses ahead with 'operationalising' the nuclear deal.

(The nuclear deal can be operationalised only after the consent of the Nuclear Suppliers Group, an India specific agreement with International Atomic Energy Agency and after the ratification of the 123 Agreement by the US Congress possibly by the year-end.)

Congress party leaders are assiduously creating an impression that efforts are continuing to 'persuade' Left leaders not to turn the disagreement over the nuclear deal with America into a crisis.

But they may be over-optimistic about the scope for their persuasive skill at this juncture.

They may also need to take a lesson or two on 'democratic centralism' that is the guiding spirit in the functioning of the Communist parties.

The Left is not prepared to view the deal in isolation, particularly the strategic part of it and its possible impact on foreign policy.

Left leaders argue that such a deal was not envisioned in the Common Minimum Programme. They apprehend that the deal 'locks in' India onto US global strategy, and that this is bound to get reflected, if not already, in Indian policies not only in foreign affairs but also in other spheres such as the economy, agriculture and science and technology.

But even if room for any constructive and pragmatic dialogue could take place between the government and the Left leadership, a 'not angry but anguished' Dr Singh created political tension by giving the Kolkata-based The Telegraph a sensational interview.

He told the paper, 'I told them (Prakash Karat and A B Bardhan) that it is not possible to renegotiate the deal. It is an honourable deal, the Cabinet has approved it, and we cannot go back on it. I told them to do whatever they want to do, if they want to withdraw support, so be it.'

Unsurprisingly, the Left parties felt that the prime minister was needlessly abrasive.

If the Left parties exit from the coordination committee, then the credibility of the government will be dented, and overall political stability will be shaken, and any big-ticket economic reforms will have to wait.

The Communist Party of India-Marxist politburo is meeting on Friday and Saturday where they will 'review' the entire strategy of supporting the UPA.

In the event of the Dr Singh government pressing ahead with the deal, the chances are that the Left may decide to part ways with the UPA government.

That critical day can come when the deal comes into effect.

The Left parties are raising the pressure now, because this is the critical moment in concluding the nuclear deal.

Dr A N Prasad, nuclear scientist and an expert on the safeguards agreement, told rediff.com, "The nuclear deal will come into operation after the US Congress ratifies it. No government would think of rejecting the deal after going through laborious process at the NSG, IAEA and the US Congress. The Indian government can say no to the deal now but not later. It can have bad repercussions."

The nuclear deal will come up for discussion in Parliament on August 20, where the Congress will face acute embarrassment due to the strident opposition to the deal from the Bharatiya Janata Party and the Third Front, apart from the Left parties.

The coming week will give a fair picture of the future of this government and the direction of the country's politics in coming months.

"The damage has been done," said a senior Congress leader and minister of state in the Union Cabinet.

Anxiety was writ large on the faces of the Congress MPs in Parliament's Central Hall on Thursday.

The complete failure of the 'power breakfast' meeting between CPI-M general secretary Prakash Karat and Prime Minister Manmohan Singh [Images] on August 14 has compelled them to rethink their political understanding of the Congress-Left standoff.

Within few hours of the meeting, CPI-M issued a terse statement maintaining that the PM's statement in Parliament did not shed any new light on the issue.

The strategists in the Prime Minister's Office and many Congress leaders were spreading the interpretation until now that the "Communists are opposing the deal because they have to oppose anything to do with the US."

The Congressmen, weaned on the Delhi political culture, were saying that the Left leaders' stance on the nuclear deal was predictable and it's "more about posturing."

All the same, government sources till Wednesday were hinting that in spite of the Left leaders' strong stand, the government will sign the deal and will make it operational after the necessary agreements come through with the NSG and the IAEA.

But the prime minister's interview revealed the extent of the resistance to the deal and happenings behind closed doors in New Delhi.

The tussle between Left parties and Congress over the nuclear deal has stalled Parliament.

The Congress has been politically isolated and is entering a completely unpredictable zone where they will remain unsure how the nuclear deal issue will be played out in popular imagination.

So far, most Congress leaders rediff.com talked to tended to believe that the nuclear deal cannot become an election issue and that the Left's 'problem' is with America rather the civil energy nuclear deal.

The two main players in the current political deadlock are Dr Singh and Karat. Both have diametrically opposite agendas and issues.

Karat is ideological, honest and has blind conviction in his political stance. He will never like his or his party's name to be even indirectly associated with the nuclear deal.

He feels that his party's identity gets tarnished and its cadres may get disoriented if a government, which is solely surviving on his party's support from the outside, gets into the warm strategic embrace of the US.

The CPI-M has articulated its position after long, protracted discussions within party forums.

The CPI-M statement said that, "The bilateral nuclear agreement must be seen as a crucial step to lock in India into the US global strategic designs. Alongside negotiations for the nuclear accord, steps have been taken for closer military collaboration. The Access and Cross Servicing Agreement, otherwise known as the Logistics Support Agreement, is being pushed ahead as provided for in the Defence Framework Agreement.

"This would lead to regular port calls by US naval ships at Indian ports for fuelling, maintenance and repairs. The regular joint naval exercises have now been widened to include India in the trilateral security cooperation, which exists between the US, Japan [Images] and Australia. The September joint naval exercises in the Bay of Bengal are a major step in this direction."

"The United States is exerting pressure on India to buy a whole range of weaponry such as fighter planes, helicopters, radars and artillery involving multi-billion dollar contracts. The aim is to ensure 'inter-operability' of the two armed forces."

On other hand, Dr Singh who is always underplaying his executive and political actions and always giving party president Sonia Gandhi [Images] a chance to hog the limelight, is confusing his partymen by showing an inflexible attitude on the Indo-US relationship.

On any aspect of the strategic ties with the US, he is consistently focused and even displays an uncharacteristic swiftness.

The clever negotiation of the nuclear deal is an example of his team's resolve to reach an agreement.

It's quite noteworthy that Sonia Gandhi has given timely support to Dr Singh and the nuclear deal, while addressing the meeting of the Congress Parliamentary Party.

But the teaming up of the two most powerful leaders of the Congress to push through the nuclear deal may not be enough this time.

Making it clear that the Indo-US nuclear deal should not be operationalised, the CPI on Thursday asked the government not to take the support of the Left parties for granted.

"Don't take the support of the Left parties for granted. The Left is a serious political force and reflects the concerns of the people. The government should understand this," CPI leader D Raja told reporters outside Parliament.

In 2005, the Left parties had walked out of the co-ordination meeting and resorted to a four-month boycott following the standoff over the disinvestments of Bharat Heavy Electricals [Get Quote] Limited and the Iran nuclear issue.

The Indo-US nuclear deal is a much more serious issue because it directly challenges the fundamental political identity of the Left parties.

At present, the CPI-M has 44 members in the Lok Sabha and 10 members of Parliament in the Rajya Sabha. With 54 Left members in Parliament, the CPI-M does have enough leverage to take decisions and show its political muscle as the general elections get closer.

The world is watching India and its internal politics over the nuclear deal.

On August 14, China's People's Daily featured a front-page commentary saying, 'It is safe to predict that a substantial change has taken place in the nature of Indian-US relations despite possible turns and twists in future.'

It adds, 'It is quite obvious that the US generosity in helping India develop nuclear energy is partly due to its hegemony idea and partly due to the intention of drawing India in as a tool for its global strategic pattern.'

Dr Singh must have realised by now that even 'posturing' is part of real politics.

He telephoned West Bengal Chief Minister Buddhadeb Bhattacharya in an effort to mend fences and put across his point of view so as to resolve the issue.

May be, it's too late. The damage has been done, as his colleague said.

The dice might have been cast already when he challenged the Communists through a newspaper interview.

That was no way to treat an ally, after all.