Speaking in a Holyrood debate on oil and gas, Highland MSP Rhoda Grant said that a new tax might have to be levied on the industry leading to different levels of tax north and south of the border.
Former finance ministers Jack McConnell MSP, Andy Kerr MSP and Tom McCabe MSP told the Finance Committee the tartan tax was fully functioning and ready to implement within its ten month operating window, when they were in power from 1999 - 2007.