Government urged to rule out GST changes

The prime minister is again being asked to rule out changes to the GST, after the release of a discussion paper into reforming the federation.

Giving the states and territories GST revenue based on population with a top-up given to smaller states, was flagged in the release on Tuesday afternoon.

Federal Labor said the paper makes it clear changes to the tax requires the endorsement of the commonwealth in order to proceed.

"Tony Abbott must rule out, in any circumstances, the federal Coalition supporting changes to the base or rate of the GST," Shadow Treasurer Chris Bowen said.