Prime Minister Tony Abbott predicts his government will face another "long, hard slog" in the Senate to pass budget savings but says he has not lost his drive for difficult policy reform.

Mr Abbott returned from holidays on Tuesday with a vow to push ahead with plans to introduce more price signals into the health system and deregulate university fees.

Mr Abbott also acknowledged there had been "vigorous discussions" within cabinet's powerful Expenditure Review Committee about a proposed $20 rebate cut for short GP consultations.