The Greens have developed a plan to pry open the Commission of Audit, set up by Treasurer Joe Hockey to come up with spending cuts ahead of the budget.
They will ask the Senate to establish a select committee to oversee the work of the commission.
If backed by Labor, the committee would expose deliberations the government had intended to keep secret until the budget in May.
The move came as Mr Hockey paid tribute to the Greens after using their votes to get a bill to abolish the government debt ceiling through both houses of Parliament.
''When called on to increase the limit … all Labor could do was play politics,'' he said.