While he has plenty of critics at home, Rajan is a favourite among foreign investors and has been credited for bringing inflation under control.
Even before Prime Minister Narendra Modi swept to power in 2014, Subramanian Swamy was agitating for Rajan's removal.
The bill seeks to ensure health-care, treatment and rehabilitation of persons with mental illness "in a manner that does not intrude on their rights and dignity."
It makes it mandatory for companies to spend on social welfare and seeks to bring in greater transparency.
A top Home Ministry official said no note has been prepared yet to be placed before tomorrow's scheduled meeting of the Cabinet to be chaired by Prime Minister Manmohan Singh.
Even as Sonia Gandhi was on Saturday re-elected chairperson of the Congress Parliamentary Party and asked party men not to bicker in public amid a fierce blame game in the party, the anger and anguish was visible after the meet was over. Anita katyal reports