Left parties on Wednesday objected to several clauses in the bill for implementation of the Indo-US nuclear deal, including enlisting India's support to "contain Iran" and conditions on nuclear test.
Left criticised, saying they "completely contradict" the assurances given by the UPA government.
CPI(M) and CPI, which provide key outside support to the Congress-led coalition, expressed strong reservations over the clauses in the bill and asked the government not to deviate from its stated foreign policy commitments and positions under American pressure.
"The bill makes a specific reference to securing India's 'full and active participation' in the US efforts to dissuade, isolate and if necessary sanction and contain Iran for seeking nuclear weapons."
"This clearly substantiates the CPI(M)'s apprehensions that through the nuclear deal, US will arm twist India to change its foreign policy to know tow to US strategic global designs," the party Polit Buro said in a statement.
It also slammed clauses in the bill which seeks to push New Delhi to comply with the Fissile Material Cut-off Treaty (FMCT) saying that the Presidential waiver will "cease to be affective" if India conducts a nuclear test.
"India's unilateral moratorium on conducting nuclear tests cannot be subservient to such US conditionalities. India's sovereignty on these matters cannot be compromised," it said.