Howling and shouting, opponents of India's much-touted nuclear deal with the US disrupted parliament hours before the prime minister was to address the house on the pact.
The deal reverses three decades of US policy by allowing the US to send nuclear fuel and technology to India, which has refused to sign major international nonproliferation accords and has tested atomic weapons.
Since the broad deal was first announced in July 2005 it has been praised as a cornerstone of an emerging partnership between India and the US after decades on opposite sides of the Cold War divide.
New Delhi and Washington agreed earlier this month on the technical details of how the nuclear cooperation would work, finalizing a so-called 1-2-3 agreement that Prime Minister Manmohan Singh was to speak about in parliament yesterday.
India got much of what it wanted in the deal, including the right to stockpile and reprocess atomic fuel. But Singh's communist political allies, who oppose closer ties with the US, remain skeptical of the pact, as do right-wing opposition parties.
Yesterday, lawmakers from the Samajwadi Party, a regional party in northern India that also opposes closer ties with the US, stormed to the floor of parliament's lower house, shouting "Cancel the nuclear deal!"
The lawmakers refused to return to their seats and the session was adjourned until 2pm, where Singh was scheduled to speak.
Samajwadi party and other right-wing opposition parties have no chance of defeating the deal, which does not need to go before parliament. But the communists, whom the government depends on for its majority, could destabilize the coalition government by withdrawing their support for the ruling Congress party.
However, analysts said it was highly unlikely the communists would bring the government down because they stand to lose too much if the opposition Hindu nationalists return to power.
US critics, meanwhile, worry the deal will stymie US anti-proliferation efforts, especially in Iran.