Tony Abbott must use this weekend's State Liberal Conference to once-and-for-all rule out any changes to the current GST distribution system, the Premier, Lara Giddings said today.

Ms Giddings said Tasmanians remained deeply concerned about Mr Abbott's repeated refusal to rule out changes that would rip up to $700 million a year out of Tasmania.

"Those fears have been compounded in recent days, with Tasmanian Liberal Senators voting against a motion endorsing the principles of fairness that underpin the distribution of GST revenue," Ms Giddings said.

"Tasmanian Liberal Senators have shown they're clearly more interested in Tony Abbott's best political interests, than the interests of all Tasmanians.

"And Will Hodgman has shown that he lacks the backbone and the clout to stand up to Mr Abbott and tell him to keep his hands off Tasmania's fair share of the GST.

"It appears it will be left to rank and file Liberal members to tell Mr Abbott that they won't be sold-out in pursuit of votes in the big mainland states."

Ms Giddings said Mr Abbott's shifty approach to the GST issue stood in stark contrast to Federal Treasurer Wayne Swan who fully committed to the important principle of Horizontal Fiscal Equalisation at the Labor State Conference earlier this month.

"Anything short of the same unequivocal statement from Tony Abbott will prove once and for all that he is no friend of Tasmania."

Ms Giddings said the Federal Liberal Leader had an inglorious record when it came to supporting Tasmania and had openly mocked the state at the recent South Australian Liberal Conference.

"His plans to change the GST system would cost Tasmania the equivalent of 800 doctors, 3000 nurses, 500 allied health professionals and over 100 child protection staff every year.

"His plans to rip up the NBN would cost Tasmania 800 jobs in the rollout and first mover advantage in the new digital economy.

"His promise to repeal the price on carbon if he is ever elected as Prime Minister, would cost Tasmania up to $70 million per annum.

"Furthermore, he has sold out the Tasmanian forest industry by refusing to support legislation to ban illegal logging and to restrict the importation of illegally logged timbers into Australia."