Labor will hike taxes: PM

Prime Minister Tony Abbott claims Labor has "let the cat out of the bag" and revealed potential plans to hike taxes if elected into government.

Shadow treasurer Chris Bowen has declared the era of "Santa Claus" politics over, admitting tough decisions would have to be made to return the budget to surplus.

The Australian people don't believe in an opposition that pretends to return to surplus without spending cuts and tax increases, he said.

Mr Abbott is calling on Labor to reveal its tough decisions instead of merely blocking budget measures such as the Medicare changes in the Senate.

Opposition leader Bill Shorten says he will release Labor's tax policies "in good time" before the 2016 election but prefers targeting big business over GP taxes and university overhauls.