Assistant ministers set for promotion in cabinet rejig

The two senators from Labor's Left faction will all but certainly move up from assistant ministries following the retirement of Linda Burney and Brendan O'Connor at the next election, due by May 2025.

It puts two new frontbenchers in the Senate following calls to bring more ministers into the upper house to help share the workload during busy weeks.

Tasmanian senator Carol Brown will step back from her assistant ministry portfolio due to health reasons, leaving three assistant spots open following the promotions.

Prime Minister Anthony Albanese will announce his new-look ministry in Canberra on Sunday before they're sworn into their roles on Monday.

Assistant Minister for Indigenous Australians Malarndirri McCarthy is widely touted to take over Ms Burney's role.

It would open up her assistant role for Indigenous MPs Marion Scrymgour or Jana Stewart as a handful of backbenchers jostle for a promotion.

A delicate factional balance needs to be maintained under internal Labor processes, with all retirements from the Left.

Assistant ministries are decided by the prime minister, with questions over whether all three Left spots will be handed back to the same faction or whether one will go to the Right to counterbalance a slight under-representation.

Victorian MP Kate Thwaites has shaped up as a strong contender, with other names including Ged Kearney, Josh Wilson or the Right's Andrew Charlton.

Andrew Giles is expected to be dropped from the immigration portfolio after coming under fire for his handling of a High Court case that led to some 150 former detainees being released after indefinite detention was ruled unlawful.

There is speculation Home Affairs Minister Clare O'Neil could be moved on after being embroiled in the fallout of the court case.

Neither is expected to be dumped entirely but rather moved sideways despite calls from the Opposition to flick them to the backbench.

Deputy Prime Minister Richard Marles would not pre-empt the speculation on Sunday but backed Mr Giles and Ms O'Neil as " very good ministers".

He also paid tribute to his three colleagues stepping back from leadership roles.

"All three have had fantastic careers over a very long period," he told Sky News.

Opposition home affairs spokesman James Paterson was less congratulatory about his counterpart and immigration minister, saying moving them on would be "an admission of failure and admission of fault by the prime minister".

"A starting point would be to sack both of them and get new people in those portfolios," he said.

"A lot of Australians will be hoping for that given the chaos that we've seen over the last two years."

Australian Associated Press