In a veiled threat to the UPA, the CPI(M) on Sunday said the Congress should realise it has only 145 MPs and not act in haste on the nuclear deal issue as the government is "running on the Left's critical support".
It also accused the UPA of not adhering to the Common Minimum Programme chalked out with the allies and "adopting a US agenda".
"The nuclear deal is for 40 years and there should be no haste in signing it... They (UPA) must remember that Congress has just 145 MPs and the Central government is running on the Left's critical support," CPI(M) General Secretary Prakash Karat said addressing a convention on Indo-US civilian nuclear deal here.
He said Prime Minister Manmohan Singh would have to decide whether "he would like to go with us, his allies and the people of the country, or prefer to toe the US line".
A debate was already on on whether the government should sign the deal and it would be better to see what the next dispensation in the US felt about it, he said.
"US President George Bush is himself not popular and only 30 per cent of the people support him. So why should we dance to his tunes?," Karat said.
He said the Congress leadership was aware of the Left's opposition to the deal and should not move an inch further. "Wait for six months and have a detailed debate on the issue in Parliament".
"Can a minority government deal in such a manner... We have no faith in you. The nuclear deal is not in our interest and we will never accept it," he said.