Talks between India's Congress-led ruling coalition and communist allies over a nuclear deal with the US have ended with no indication of progress.
There have been isolated protests against the nuclear deal
There are growing signs that the government may shelve the deal. The two sides will resume talks on 16 November.
The communists say the deal would give the US too much influence over India's foreign policy.
They have threatened to end support for Prime Minister Manmohan Singh, which could trigger an early election.
The deal would give India access to civilian nuclear technology and fuel even though it has not signed the nuclear Non-Proliferation Treaty.
US companies are hoping the deal would pave the way for lucrative contracts in India.
The administration of US President George W Bush is keen for the deal to be completed before next year's presidential elections.
Monday's talks were held in a "constructive and cordial atmosphere", Foreign Minster Pranab Mukherjee told reporters.
Prime Minister Singh told Mr Bush recently that he was having difficulty implementing the deal.
It was the first clear sign India could abandon it.
The communists were expected to ask the government during Monday's talks to confirm that the deal had been shelved.
"They are changing their position every day. We would like to know what the stand of the government is," D Raja of the Communist Party of India told Reuters news agency.
After many weeks during which the Indian government insisted it would press ahead with the deal, Mr Singh's conversation with Mr Bush last week pointed to the government backtracking in the face of opposition.
But on Thursday Mr Singh told reporters on the sidelines of an official trip to Africa that attempts were being made to evolve a "meaningful consensus" on the issue.
The prime minister called Mr Bush last week and told him that "certain difficulties have arisen with respect to the operationalisation of the India-US civil nuclear co-operation agreement".
He said the nuclear agreement was "an honourable deal that is good for India and good for the world".
He said, however, that if the deal did not come through, he would be disappointed - but he could live with it.
The landmark deal has also been criticised by many outside India.
Under the agreement, India is allowed to reprocess spent nuclear fuel - something that is seen as a major concession and opposed by some members of the US Congress.