The Bill, which amends the Citizenship Act, 1955 to make illegal migrants in select categories eligible for citizenship, has been attacked by the opposition, minority outfits and others for leaving out Muslims and also on the ground that it is at odds with the Constitution, which does not differentiate between citizens on the basis of their faith.

The Bill has been opposed vehemently by opposition parties like Congress, Trinamool, DMK, Samajwadi Party, RJD and the Left and even regional parties like BJD have expressed reservations.

The Bill has sparked resentment in the northeast, and there are indications that the government is working out a compromise intended to reassure states in the region over the implications of granting citizenship to a large number of Hindus who have come from Bangladesh over the decades.