The Congress core group met in New Delhi on Sunday evening ahead of the deliberations of the United Progressive Alliance constituents to find a way out on the stand off with Left parties on the civil nuclear deal with the US.

The core group, headed by Congress chief Sonia Gandhi [Images], includes Prime Minister Manmohan Singh [Images], senior ministers Pranab Mukherjee, Shivraj Patil, A K Antony and political secretary to Gandhi, Ahmed Patel.

The core group meeting is understood to have discussed the suggestion by the Communist Party of India-Marxist that a mechanism be set up to study the implications of the Henry Hyde Act on the sovereignty of the country.

On Saturday, the Left parties had served an ultimatum to the government on the civil nuclear deal warning it of "serious consequences" if it was operationalised.