NEW DELHI (AFP) - A bloc of Indian left-wing and communist parties announced Tuesday they were pulling out of the country's coalition government in protest against a nuclear energy deal with the United States. Their decision, however, was not expected to cause the collapse of the Congress-led government of Prime Minister Manmohan Singh, who last week managed to win support from a regional party to avoid the prospect of early elections. Marxist leader Prakash Karat told reporters in New Delhi that the "time has come" for India's leftists to bail out of the coalition in the wake of Singh's decision to push ahead with implementing the controversial pact. "We have decided to ask the president for an appointment so that we can formally withdraw support tomorrow," said Karat. The Press Trust of India said the parties will ask President Pratibha Patil to order confidence vote in parliament. But Singh, currently in Japan for a meeting of the Group of Eight industrialised nations, said the government of the world's second most populous nation was not in danger. "I don't think it will affect the stability of our government," Singh told reporters. In New Delhi, Congress spokesman Manish Tiwari added the reshaped coalition "will prove that it has the numbers in the parliament." Singh's administration is seen as unlikely to collapse thanks to a deal struck last week with the regional socialist Samajwadi Party. "We have 39 MPs and we have some others who have pledged to vote with us, for the government," Samajwadi Party leader Mulayam Singh told reporters. Political analyst Yashwant Deshmukh said the walkout by the left-wing parties was now largely symbolic. "Right now with the support of the Samajwadi Party, it seems the government will last its term and the deal will also go through," he said. Meanwhile, the White House warned Tuesday that time was running short to ratify a landmark US-India civilian nuclear agreement during US President George W Bush's term, which ends in January. Speaking on the eve of Bush's talks at the mountain resort of Toyako with Indian Prime Minister Manmohan Singh, spokeswoman Dana Perino said the US Congress had a heavy workload and "a limited number of legislative days." Perino brushed aside a question about whether Singh was expected to announce that he is ready to move ahead with the agreement, saying it was "premature to say" before the leaders met on the margins of a rich nation summit. "But obviously we've maintained a strong commitment to carrying through on our side of the deal, and obviously India has had a lot of discussion among its political parties," she told reporters. "It's been a long road, and there's been a healthy debate," Perino said. "We'll have to see what he's able to bring on the India civil nuclear agreement," she said. "It could be that he's ready to move forward - but it also could just as likely be that they have a little bit more work to do." "But we obviously recognise as well that we have a limited number of legislative days for our congress to get a lot of work done," said the spokeswoman. Singh arrived Monday in Toyako, where he was expected to tell Bush he will move ahead on the stalled nuclear cooperation accord despite tough opposition.