The reshuffle was triggered by the retirement of former finance minister Mathias Cormann, who is making a tilt for the role of OECD secretary-general.

Trade Minister Simon Birmingham has taken on Mr Cormann's finance role as well as leadership of the government in the Senate.

But it is widely expected Education Minister Dan Tehan - a former diplomat - will shift into the trade role, which is taking prominence as Australia seeks to rebuild ties with China and look to other markets to export goods.

With the aged care system undergoing major change and awaiting a royal commission report early in the new year, there is talk the portfolio currently held by Tasmanian senator Richard Colbeck could be elevated to the cabinet.

Senator Colbeck told reporters this week he was "keen to continue in the role" and had spoken with Mr Morrison about it.

Despite earlier speculation about major changes in security portfolios, Defence Minister Linda Reynolds, Home Affairs Minister Peter Dutton and Foreign Minister Marise Payne are all expected to retain their jobs.

However their department secretaries are likely to play musical chairs.

Health Minister Greg Hunt said this week he had the prime minister's endorsement to continue in his role, as the coronavirus pandemic response remains a government priority.

Mr Morrison also must resolve the future of Immigration Minister David Coleman, who has been on personal leave for 12 months during which time Alan Tudge has been acting in the role.

There is speculation former cabinet minister Bridget McKenzie could return to a key post, while others in the mix include Victorian senator Jane Hume and West Australian MP Ben Morton, who has worked closely with Mr Morrison on the coronavirus response.

The prime minister plans to take a break with his family in January, hoping to spend some time relaxing on the NSW south coast.

Labor leader Anthony Albanese is waiting for the prime minister to make an announcement before he unveils his opposition frontbench shake-up.

Australian Associated Press