Suitable legislation for the levy of GST (Central GST Bill, Integrated GST Bill and State GST Bills) drawing powers from the Constitution would need to be passed by the Parliament and the State Legislatures. Unlike the Constitutional Amendment which requires 2/3rd majority, the GST Bills would need to be passed by a simple majority. Obviously, the levy of the tax can commence only after the GST law has been enacted by the Parliament and respective Legislatures.