The changes, driven by the loss of Assistant Ministers Wyatt Roy and Peter Hendy and the likely loss of Tourism Minister Richard Colbeck, will be announced after the Liberal party room and then Coalition party room meet in Canberra for the first time since the July 2nd federal election.

Several Coalition MPs told Fairfax Media they expected colleagues to vent their anger about the government's $6 billion package of superannuation changes contained in the May budget, with particular concern to be raised about a proposed $500,000 cap on non-concessional super contributions, which has been backdated to 2007.

Liberal campaign director Tony Nutt and pollster Mark Textor will also address the gathered MPs about the Coalition's campaign and, in the words of one, "they will have to show remorse" for the party's reduced majority.

Mr Turnbull indicated on Friday that the junior Coalition partner, the Nationals, would pick up two ministries as their proportional share of MPs in the party room had grown following the defeat of a swag of Liberal MPs but wholesale changes to the front bench are not expected.

Nationals senator Matthew Canavan is widely tipped to move from the outer ministry to the cabinet but on Sunday, Coalition MPs were speculating about whether the Nationals would pick up an additional spot in the outer ministry or assistant ministry, or even two assistant ministry positions.

Some Nationals told Fairfax Media on Sunday they believed assistant minister Michael McCormack could be promoted to the outer ministry, while others said that one or two of Andrew Broad, David Gillespie, Bridget McKenzie or George Christensen could instead be promoted from the back bench to the assistant ministry.

And while the junior Coalition partner jostled for positions, Liberals said the Prime Minister had to be mindful of the need to promote younger conservative MPs such as Zed Seselja or Michael Sukkar after closing the door - repeatedly - on a return to the front bench for former prime minister Tony Abbott.

One MP said that promoting two conservative Liberals would "keep the wolves away from the door" for the Prime Minister, but any less than that could trigger further unrest in the party room.

Some changes to ministerial portfolios are also tipped, with suggestions that Assistant Treasurer Kelly O'Dwyer could lose her small business portfolio to the Nationals - though she would remain in cabinet - while Immigration Minister Peter Dutton is tipped to return to cabinet's national security committee, which he sat on until the September 2015 leadership change.

Cabinet and the outer ministry are limited to a total of 30 places, while there can be no more than 12 additional assistant ministers.

Mr Turnbull confirmed again on Sunday that Mr Abbott would not be returning to the front bench and added that "such changes as there are to the ministry will be announced tomorrow afternoon".

Ahead of the party room meeting Liberal senator David Johnston, who looked set to lose his seat in the upper house once counting is finalised, said the prime minister "should reassess" backdating the $500,000 cap to 2007, amid reports that Treasurer Scott Morrison could broaden exemptions on the cap.

Mr Turnbull has previously said that there would be no changes to the "ironclad" suite of proposals, despite some Liberals claiming the policies hurt the party's base, cost donations and even votes during the election.

But on Sunday the prime minister, who lost a swag of seats in the election and will hold at most 77 in the 150 member lower house if Herbert MP Ewen Jones hangs on, said he was listening "very keenly" to the concerns inside his party.

"The reforms are important, but in the implementation and transition, there is work to be done," Mr Turnbull said. "There always is with tax changes. They will go through the normal cabinet and party room process."

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