Mr Wilkie secured $340 million to redevelop the hospital as part of a deal in exchange for his support for a Labor federal government.

The Australian Medical Association yesterday slammed the deal, which also locks the state government into spending $225 million over six years, while at the same time budget cuts are forcing hospital wards to close and a reduction in the number of elective surgeries.

Under the Commonwealth Grants Commission process the federal government's $340 million contribution will be taken into consideration when it works out how much GST revenue the state will receive.

State president John Davis called on Mr Wilkie to negotiate an exemption from the process or resign.

``The funds Mr Wilkie achieved, in order for Ms Gillard to become prime minister, were nothing more than an advance on our pocket money from Canberra,'' Dr Davis said.

The AMA has estimated the state will get to keep just $12 million, with the rest clawed back through reduced GST receipts.

``As elective surgery in Tasmania is being cut and health workers sacked, Tasmanians were under the false belief that the RHH redevelopment funding was additional to the state coffers,'' Dr Davis said.

The full impact of the $340 million grant on the state's GST revenue won't be known until March and will be spread over three years.

Mr Wilkie dismissed the AMA calculations as premature and said the government would end up with much more money in its pocket.

But his comments are also at odds with the state government's calculations.

Last month, Premier Lara Giddings confirmed ``there will be no significant net financial benefit to the state''.

Treasury secretary Martin Wallace yesterday supported the redistribution process to ensure fairness.