The Left parties on Thursday launched a scathing attack on the government for approaching the International Atomic Energy Agency for the safeguards agreement in the nuclear deal before a trust vote in Parliament, terming the move as a "shocking betrayal of a moral commitment" made to the country.

"We know how to fight against the deal and we will make it politically impossible for the government to go ahead with the agreement," Communist Party of India-Marxist general secretary Prakash Karat told reporters in Delhi in the presence of his CPI counterpart A B Bardhan and other senior Left leaders.

Noting that it was a "blatant violation of the assurance" given by the government (that it will seek a confidence vote before going to IAEA), Karat said the move was "nothing but a shocking betrayal of moral commitment not only to the Left parties, but to the country and people. In less than 24 hours, when the country knows that the government is reduced to a minority, the text (of the IAEA agreement) has been submitted."

The Left leaders wondered how the government changed its position to approach the IAEA in less than 24 hours of External Affairs Minister Pranab Mukherjee announcing that the ruling coalition would seek a vote of confidence in the wake of Left parties withdrawing support.

"There is no reason to doubt the integrity of Mukherjee who said that he had consulted the prime minister before telling the nation that the government would seek a confidence vote," Karat said.

He said the Left parties want the prime minister to tell the nation "what transpired in the meeting he had with US President George W Bush [Images] (in Japan [Images]) which led to the going back on a public pledge (that they will seek a vote of confidence)."