Government plans to bring forward $2.4 billion in revenue from changes to the Petroleum Resources Rent Tax will not be resolved until next year, and the government has rejected suggestions that the delay will erode the potential savings.

With just one more week of parliament before the end of the year, and the Greens and the Coalition each making demands the government cannot meet, any Senate consideration of the changes has been deferred until the pre-budget sittings in February and March at the earliest.