Greg Hunt has been named Australia's new Health Minister as part of Prime Minister Malcolm Turnbull's fourth reshuffle since taking the top office.

Key points: Hunt appointed Health Minister; Sinodinos takes on Industry, Innovation and Science

Hunt appointed Health Minister; Sinodinos takes on Industry, Innovation and Science Ken Wyatt becomes first Indigenous person in Commonwealth ministry as Minister for Indigenous Health and Aged Care

Ken Wyatt becomes first Indigenous person in Commonwealth ministry as Minister for Indigenous Health and Aged Care Michael Sukkar promoted to Assistant Minister to the Treasurer

Michael Sukkar promoted to Assistant Minister to the Treasurer Cabinet to reduce by one position

Mr Hunt has taken over the role from Sussan Ley, who resigned from the Cabinet last week amid an ongoing expenses scandal.

Mr Hunt will also take on the role of Sports Minister, also previously held by Ms Ley.

Mr Turnbull praised his "policy, analytical and communication" skills.

"He is ideally suited to take on the very important, critically important front line portfolio of health and sport," he said.

Mr Hunt took over the industry, innovation and science portfolios from Christopher Pyne in July, bringing to an end almost a decade working in the environment portfolio.

As well as a variety of environment related shadow roles, he has previously served as environment minister, acting cities minister, parliamentary secretary to the foreign affairs minister and parliamentary secretary to the environment minister since his election in 2001.

Last year, he was awarded the inaugural Best Minister in the World award at the World Government Summit hosted by the United Arab Emirates.

The four-day trip for the summit cost taxpayers more than $32,300.

Sorry, this video has expired Malcolm Turnbull names Greg Hunt Health Minister

Mr Hunt also made international headlines in 2014 after telling the BBC that he used Wikipedia to research climate change.

Mr Hunt said he was honoured to take on the role, citing his "genuine passion" for health.

Speaking to reporters at Frankston Hospital — where his mother previously worked as a nurse — he emphasised the Government's commitment to Medicare.

"I have, and we have, a rock solid commitment to the future of Medicare," he said.

"It is simply indispensable."

Mr Hunt also highlighted mental health as an area of focus, saying he intends to make it a "critical part" of his role.

Labor's health spokeswoman Catherine King urged Mr Hunt to lift the freeze on the Medicare benefits schedule in his new role.

"Malcolm Turnbull has changed his salesperson when it comes to health, but he hasn't changed a single one of his policies," she said.

Greens leader Richard Di Natale criticised the appointment, saying, "Greg Hunt nearly killed the Great Barrier Reef, imagine what he's going to do to our health".

Concerns over Sinodinos' involvement with ICAC

Arthur Sinodinos, who has been acting health minister since Ms Ley stepped down, will now take over the industry, innovation and science portfolios.

Since being appointed Cabinet Secretary in 2015, the highly regarded senior member of the Government has been privy to high-level discussions and decisions by the Turnbull Government.

Despite his standing, some within the Coalition have raised concerns over elevating Senator Sinodinos, given his involvement with the Independent Commission Against Corruption (ICAC).

Senator Sinodinos stepped down from his role as assistant treasurer amid the corruption inquiry in 2014.

ICAC was investigating Australian Water Holdings (AWH) amid claims Senator Sinodinos, a former AWH director and NSW Liberal Party treasurer, stood to make up to $20 million from a contract with the state-owned Sydney Water Corporation in January 2012.

No corruption findings were made against Senator Sinodinos, who last year refused to front a senate committee investigating political donations focusing on the fundraising activities of the NSW branch of the Liberal Party.

Senator Sinodinos joined federal politics in 2011, appointed after the resignation of Helen Coonan before being elected in 2013.

First Indigenous appointment to Commonwealth ministry

Ken Wyatt has been promoted to Minister for Aged Care and Minister for Indigenous Health. ( ABC News: Andrew O'Connor )

Senator Sinodinos' former role will be taken over by the Prime Minister's office, reducing Cabinet by one.

Ken Wyatt has also been promoted from Assistant Minister for Health and Aged Care to Minister for Aged Care and Minister for Indigenous Health.

Mr Wyatt is now the first Indigenous person appointed to the Commonwealth ministry.

Michael Sukkar has also been appointed as Assistant Minister to the Treasurer.

Mr Turnbull said the new ministers would be sworn in by the Governor-General in Canberra on Tuesday.

"This is not a large reshuffle," he said.

Cultural change surrounding expenses

Mr Turnbull also used the press conference to highlight the "big cultural change" he intended to introduce in terms of parliamentary entitlements.

"We need to have greater transparency, greater accountability, monthly reporting will be very important," he said.

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

His comments come little more than a week after Ms Ley stepped aside from Cabinet amid two investigations into her travel expenses, which included billing taxpayers to attend two New Year's Eve events hosted by a prominent Queensland businesswoman and donor.

Ms Ley was also criticised for purchasing a $795,000 luxury apartment on the Gold Coast while on a taxpayer-funded trip, claiming it was an impulse purchase.

When asked several times about the investigations into Ms Ley's expenses over the past week, Mr Turnbull said the report would not be made public.