Prime Minister Malcolm Turnbull has announced that Victorian MP Greg Hunt will replace Sussan Ley as health and sport minister.

Stand-in health minister and cabinet secretary Arthur Sinodinos will step into Mr Hunt’s vacated role as industry, innovation and science minister.

Ms Ley resigned as health minister on Friday due to the fallout from the parliamentary expenses controversy.

“He [Mr Hunt] has strong policy, analytical and communication skills, developed over a very long front bench career,” Mr Turnbull said.

“During his [Mr Hunt’s] time as the environment minister, he demonstrated an ability to grapple with extremely complex policy issues and engage a very diverse range of stakeholders and interest groups … He is ideally suited to take on the very important, critically important front line portfolio of health and sport.”

As Mr Turnbull made the announcement, he faced his highest disapproval rating (48 per cent) since becoming Prime Minister in July.

It is believed Mr Sinodinos – a key numbers man in Mr Turnbull’s 2015 operation to depose Tony Abbott – was overlooked for the permanent health role because he sits in the Senate and would be unable to sell or defend the government’s case for health reform on the floor of the lower house.

Health is an area of vulnerability on the back of the opposition’s ‘Mediscare’ campaign during last year’s election.

A pressing challenge for the new health minister will be to decide on private health insurance premium rises, starting in April.

Arthur Sinodinos is a staunch Turnbull ally.

The PM also announced that Ken Wyatt will become minister for aged care and minister for indigenous health. He was previously assistant minister for aged care.

This makes Mr Wyatt Australia’s first ever indigenous minister.

Michael Sukkar has also been appointed as assistant minister to the Treasurer.

On the parliamentary expenses controversy that is engulfing the government and led to Ms Ley’s resignation, Mr Turnbull was emphatic.

“I will shake this up, I can tell you. There is a big cultural change on the way. It is underway already,” he said.

Mr Turnbull has already announced sweeping changes to the parliamentary entitlements system will be made soon. Many have criticised the family travel entitlements afforded to politicians and the flimsy rules around claiming work and travel expenses.

Opposition Leader Bill Shorten derided the prospect of the government “recycling dodgy Senator Sinodinos”, saying Mr Turnbull simply “did not want to bring Tony Abbott back into the cabinet”.

Mr Abbott asked Senator Sinodinos to briefly stand aside in 2014 while the NSW Independent Commission Against Corruption looked into a company in which he was  formerly an office holder.

Senator Sinodinos has consistently denied any wrongdoing.

Shadow health spokeswoman Catherine King said it would “not matter who the new (health) minister is, they have got a pretty poor agenda in health and each one of them has just been implementing what Malcolm Turnbull has been telling them to do”.

#funfact Greg Hunt, the subject of most recent speculation on who'll replace Sussan Ley as health minister, is married to a surgical nurse.

— Sean Parnell 🫶🏼 (@seanparnell) January 17, 2017

If Greg Hunt performs as well in Health as he did in Environment, several hospitals will be bulldozed and a pandemic will break out

— Ben Eltham (@beneltham) January 17, 2017

Mr Turnbull, who has undertaken a tour of regional Queensland in the past two days was reportedly keen to reduce the 23 members in his cabinet – the most since the Whitlam government in 1975.

It is possible the cabinet secretary position would then be filled by a senior public servant, reducing the size of his cabinet by one.

Upon being elected Prime Minister last July, Mr Turnbull said Mr Hunt had been “outstanding” in his previous role as Environment Minister. Last February, a panel established by Thomson Reuters for the 2016 World Government Summit of Dubai named Mr Hunt its “Best Minister in the World”.

Coalition MP slapped down by PM

Meanwhile, Mr Turnbull has slapped down one of his backbenchers, Andrew Laming, in the wake of the Brisbane MP’s ill-advised social media post questioning teachers’ work ethic.

Andrew Laming did not endear himself to the education sector with his Facebook post.

Dr Laming was the centre of controversy last week when he asked on his Facebook page whether teachers were “back at work this week, or are they ‘lesson planning’ from home? Let me know exactly”. Mr Laming, who was on holidays at the time, later deleted the post.

Mr Turnbull told ABC Radio that his teacher daughter “certainly had some concerns and next time I see (Dr Laming) I will pass them on to him”.

“My daughter Daisy is a school teacher and she had a very strong reaction. So I think Andrew will have received some very emphatic feedback from teachers in his electorate and elsewhere,” Mr Turnbull said..

“I have to say, of course I am biased, I suppose, with a school teacher daughter, but teachers work very hard; they are absolutely at the front line of our future because it is teachers – charismatic, hardworking teachers – that change lives.”

Mr Turnbull said he considered himself a “passionate” supporter of the teaching profession. School funding will be a pressing issue for the government in 2017, as it negotiates a new funding model to replace Labor’s Gonski model.