The NSW Liberal Party has forfeited a political donation it received from a property developer in 2015 despite the Premier saying "nothing untoward" had occurred.

Key points: The NSW Liberal Party has handed back a $1,750 donation from property developer Ming Shang

The NSW Liberal Party has handed back a $1,750 donation from property developer Ming Shang Political donations from property developers are illegal in NSW

Political donations from property developers are illegal in NSW Speaking earlier today, the Premier denied any electoral funding laws were broken

In a revelation that could see donations involving the NSW arm of the Liberal Party come under further scrutiny, Electoral Commission documents reveal the party received a $1,750 donation from property developer Ming Shang in February 2015.

Mr Ming made the contribution after attending a dinner with Drummoyne MP and Sports Minister John Sidoti, at a time when he was NSW Parliamentary Secretary of Planning.

Political donations from property developers are illegal in NSW, along with other industries such as tobacco, liquor and gambling.

On Wednesday afternoon the Liberal Party confirmed to the ABC it had become aware of the "incorrectly received donation" and had been working with the NSW Electoral Commission to forfeit it.

"The NSW Liberal Party takes our obligations under the state electoral funding and disclosure laws very seriously," a spokesman said.

The Independent Commission Against Corruption — which is in the middle of investigating NSW Labor over its political donations — would not confirm whether an investigation into the donation had begun.

Planning and Public Spaces Minister Rob Stokes on Wednesday told a parliamentary committee he would consider whether to refer Mr Sidoti to the corruption watchdog.

He said all MPs had a duty to report corruption if they believed it had occurred.

The Planning Department has agreed to "explore what information might be available" on Mr Sidoti's time as Parliamentary Secretary of Planning, between October 2014 and March 2015.

NSW Premier Gladys Berejiklian told reporters earlier on Wednesday no laws had been broken. ( AAP: Danny Casey )

But despite the admission and the forfeited donation, Premier Gladys Berejiklian today denied any electoral funding laws were broken.

"That issue has come up before and I am confident nothing untoward has occurred," she said.

'A matter for the NSW Liberal Party'

Mr Ming is vice president of Southern Han International, a property development firm building $70 million residential towers in Rouse Hill near the newly completed Metro West train line.

Mr Sidoti has declared a 10 per cent interest in the Rouse Hill development through a family company called JAFS Investment Trust.

In a statement, Mr Sidoti denied any wrongdoing.

"I comply with my disclosure obligations," Mr Sidoti said.

"Political donations are a matter for the NSW Liberal Party."

NSW Labor spokesperson Penny Sharpe said Mr Sidoti had many questions to answer.

"What briefings he received, what correspondence he was involved in, what visits he did, who he met with," she said.

"Those things should all be recorded and he should be able to provide those."

Mr Sidoti will appear before budget estimates on Thursday.