Article published on the 2008-07-08 Latest update 2008-07-08 15:48 TU
The Press Trust of India reported that the parties will ask President Pratibha Patil to order a confidence vote in parliament.
Singh told reporters in Tokyo, where he is currently attending the G8 summit, that he did not think this move would cause his government to fall.
Singh and US President George W. Bush signed an agreement to share civilian technology. Singh maintained that this nuclear pact is vital for Indian economic growth.
India currently imports some 70 per cent of its energy needs.
The 59 left-wing politicians who hold seats in the 545-member parliament, say that the deal would tie India too closely to the US, and end India's status as a major part of the non-aligned movement.
"The left had been threatening that it would pull the plug if it went to the IAEA (International Atomic Energy Agency) to begin the process of implementing the nuclear deal with the US, which must also go to US congress by the end of the year," said Vickram Roy, RFI correspondent in Delhi.
Roy added that Singh said Monday that India would go ahead with the international watchdog procedures.
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