Hours before the United Progressive Alliance-Left Committee meeting to iron out differences on the Indo-US nuclear deal, the Left parties on Wednesday rejected a compromise formula which would have allowed the government to finalise the safeguards agreement at the International Atomic Energy Agency.

Sources said the Left parties dismissed the formula as "meaningless" as they maintained that the safeguards agreement would be on auto-pilot for progress on the deal immediately after the IAEA Board of Governors approved it.

Communist Party of India-Marxist general secretary Prakash Karat met Samajwadi Party chief Mulayam Singh Yadav in Delhi on Tuesday and discussed the issue. During the 40-minute meeting, the CPI-M leader, whose party is strongly opposed to the agreement with the United States, apprised Yadav about the Left viewpoint on the issue and his discussions with Congress and several UPA allies, sources said.

Karat, earlier on Tuesday morning met External Affairs Minister Pranab Mukherjee, the government's chief negotiator on the deal, ahead of the crucial UPA-Left Committee meet. Yadav, whose party was opposed to the deal, has already made it clear that it will take Left parties into confidence before considering any re-think on the issue.

Under the formula floated by the UPA allies, the Government will go to IAEA after giving an informal assurance that it will not approach the Nuclear Suppliers Group. The Left parties want a written assurance that the government will not go to NSG after it approached IAEA for the safeguards agreement.

Mukherjee, accompanied by Defence Minister A K Antony, who was present at the meeting with Karat, drove to the residence of Congress president Sonia Gandhi [Images] to brief her on the deliberations.

Left leaders, who are unrelenting in their opposition to the agreement, were of the view that India will have no say once it seeks a waiver from the NSG which is dominated by the US.

"There is no change in our stand," Communist Party of India general secretary A B Bardhan said, adding, "If they (government) had any proposal, we would think about it".

The Left parties, supporting the UPA from outside, want the centre to fulfil the commitment given to the UPA-Left
Committee on November 16 last year that the government will not move the IAEA before the panel gives it the green signal on the issue.