Prime Minister Malcolm Turnbull announced on Monday that the secretary of the Department of Prime Minister and Cabinet, Martin Parkinson, will conduct an investigation into Ms Ley's use of taxpayer funded entitlements. 

Mr Turnbull said the Member for Farrer would stand aside without ministerial pay while the investigation is conducted. 

Ms Ley has come under fire for purchasing an $800,000 apartment on a taxpayer-funded trip to the Gold Coast in May 2015. It has also been revealed that she has taken 27 flights in and out of the Gold Coast over recent years including two trips over the New Year's Eve period. 

In her first public appearance since her entitlements attracted controversy, a defiant Ms Ley told described the affair as a "distraction" and said she expected to quickly resume her ministerial duties.

"I have nothing to hide," Ms Ley said of the investigation. "I have not broken any of the rules."

Ms Ley on Sunday apologised for making an "error of judgment" for billing taxpayers for the trip in which she purchased the apartment. She said she would repay her travel claims for that trip as well as for three other occasions when she travelled to the Gold Coast. 

She also asked the Department of Finance to examine her travel to the Gold Coast.

Mr Turnbull's cabinet secretary Arthur Sinodinos will be the acting minister for health, sport and aged care while Dr Parkinson completes his investigation.

"The secretary will thoroughly investigate the travel claims and the minister has assured me that she will promptly provide all information and assistance sought by the secretary for the purpose of this investigation," Mr Turnbull said in a statement.

"Australians expect the government to deal with these serious matters very thoroughly and in accordance with the Statement of Ministerial Standards.

"I expect the highest standards from my ministers in all aspects of their conduct, and especially the expenditure of public money."

Acting opposition leader Penny Wong said the decision to stand aside Ms Ley - rather than sack her - was "another weak response from a weak Prime Minister".

"Both Mr Turnbull and Ms Ley agree that she has breached the ministerial standards which are expected of her," Ms Wong said. 

"But instead of doing the right thing and moving to remove Ms Ley from his frontbench, to sack her from the Cabinet, we have a Prime Minister who, yet again, goes for the weak option."

At a press conference outside her electoral office in Albury on Monday morning, Ms Ley provided her first public explanation of her use of taxpayer entitlements.

"After discussions with the Prime Minister I have agreed to stand aside while his departmental secretary thoroughly investigates these travel claims," Ms Ley said.

"I look forward to working with the secretary to ensure this is done as quickly and transparently as possible and I look forward to resuming my important work in the health, sport and aged care portfolios at the earliest opportunity."

In the most detailed account of how she came to buy the Gold Coast apartment, Ms Ley repeated her original statement that the purchase was "neither planned nor anticipated".

Following a pre-budget health announcement in Brisbane on Friday May 8, Ms Ley said she decided to travel to the Gold Coast to meet with a health patient the next day to speak about access to cancer medications.

After this decision, Ms Ley said her partner Graham Johnston, who owns a bin-cleaning business on the Gold Coast, noticed an online listing for an auction on Saturday.

"I want to be very clear - my decision late Friday to attend this auction was made after I had planned to travel to the Gold Coast from Brisbane," Ms Ley said.

"I inspected this property for the first time maybe ten minutes before the auction commenced and I registered to bid. 

"I own a home here in Albury and I had gained pre-approval to purchase an investment property. 

"I had an idea of what I wanted and this apartment fit the bill. So the purchase of this particular property was neither planned nor anticipated."

Ms Ley said she had travelled to the Gold Coast over the New Year's Eve period in 2013 and 2014 for events hosted by a "prominent Queensland businesswoman".

Asked what official business she was conducting, Ms Ley said: "It was the incoming government's agenda around particular education and training issues and reflected on what the government could do to make sure that we recognised the needs of everyone in these important areas. 

"So what I'm saying is they were business conversations and they were important conversations to the future of our government's agenda."

EARLIER

Health Minister Sussan Ley has stood down from the frontbench while the secretary of the Department of Prime Minister and Cabinet, Martin Parkinson, investigates her use of taxpayer funded entitlements. 

Prime Minister Malcolm Turnbull announced she was standing aside without ministerial pay in a statement on Monday morning.

In her first press conference since the revelations about her travel to the Gold Coast emerged, Ms Ley told reporters in Albury she is confident she will be cleared of wrongdoing and will soon return to the frontbench.  

Ms Ley has come under fire for purchasing an $800,000 apartment on a taxpayer-funded trip to the Gold Coast in May 2015. It has also been revealed that she has taken 27 flights in and out of the Gold Coast over recent years - many more than her ministerial colleagues.

Mr Turnbull's cabinet secretary Arthur Sinodinos will be the acting minister for health, sport and aged care while Dr Parkinson completes his investigation.

On Sunday, Ms Ley admitted she made an "error of judgment" by charging taxpayers for a trip to the Gold Coast in which she bought the apartment and would repay the cost of four taxpayer-funded trips.

Ms Ley has also asked the Department of Finance to investigate her travel to the Gold Coast.

In his statement Mr Turnbull said: "The secretary will thoroughly investigate the travel claims and the Minister has assured me that she will promptly provide all information and assistance sought by the secretary for the purpose of this investigation.

"Australians expect the government to deal with these serious matters very thoroughly and in accordance with the Statement of Ministerial Standards.

"I expect the highest standards from my Ministers in all aspects of their conduct, and especially the expenditure of public money."

More to come