Communist allies and nationalist opponents joined forces yesterday to heckle and barrack the Indian Prime Minister as he attempted to deliver a keynote address about a landmark nuclear deal with the US.

Unfazed by the constant chanting and jeering, Manmohan Singh ploughed on through a prepared half-hour speech televised live to the nation. He had hoped to ease concerns about the controversial civilian nuclear co-operation pact that was first announced in July 2005.

Instead, his speech was drowned out by shouts of “cancel the nuclear deal”, “it’s a fraud” and “we don’t want to become American stooges” from Hindu nationalists and the Government’s Communist allies.

“You are not fit to be in parliament,” Somnath Chatterjee, the speaker, told the vocal opponents of the deal as he failed to maintain order in the chamber for the second time in one day. Earlier protests had forced him to adjourn proceedings to the afternoon session.

The raucous scenes were an embarrassment for the Congress-led Government, which has struggled to convince leftist factions — on which it depends for its parliamentary majority — of the merits of the nuclear deal.

The Prime Minister tried to calm fears that the pact, which allows the US to send nuclear fuel and technology to India after a 30-year ban, undermines India’s national sovereignty and curtails its military programme. He does not need parliamentary approval but is concerned that the issue could destabilise his coalition Government.

“The agreement does not in any way affect India’s right to undertake future nuclear tests if it is necessary in India’s national interest,” he said. “There is no question that we will ever compromise, in any manner, our independent foreign policy. India is too large and too important a country to have the independence of its foreign policy taken away by any power.”

His speech followed the finalisation last month of the so-called 123 agreement, which governs bilateral nuclear co-operation between Delhi and Washington. This allows India, which has never signed an international nuclear non-proliferation treaty, to stockpile and reprocess atomic fuel.

“I am neither given to exaggeration, nor am I known to be self-congratulatory,” Dr Singh read from his text. “I will let posterity judge the value of what we have done through this agreement. When future generations look back, they will come to acknowledge the significance of this historic deal. It is another step in our journey to regain our due place in global councils.”

In the US, the deal has attracted criticism for undermining non-proliferation efforts in Iran but is still expected to get congressional approval. Joe Lieberman, the US senator, said during a visit to Delhi at the weekend that he hoped the agreement would create “the most important bilateral relationship we have in the next century of our history”.

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