NEW DELHI, April 16: The Delhi Assembly may have to meet in May for a four-day special session to pass a few Bills which could not be finalised during the recently concluded Budget session.The House had not passed a single Bill and transacted no business except for passing the budget. The long session, which began on March 22 and ended April 12, did not pass any other resolutions except those congratulating Congress national president Sonia Gandhi and condemning the Bharatiya Janata Party at the Centre.Some of the Bills that may be passed in the session are the State Power Regulatory Committee Bill, Population Control Bill, Prohibition on Plastic Bill and a Bill on lowering the date of regularisation of unauthorised colonies to January 1, last year.While the Congress has been announcing these Bills for quite some time, it blames the bureaucracy for not keeping the deadline and scuttling the drafts of crucial Bills making it impossible to table them during the Budget session.