But the decision is expected to draw criticism of Premier Mike Baird from the opposition, Greens and independent MPs who believe Mr Cornwell should be forced out.

Mr Cornwell has admitted to a corruption inquiry that he accepted a $10,000 payment he understood to be a bribe from property developer Hilton Grugeon and used the money to pay his tax bill.

He also told the Independent Commission Against Corruption he accepted $10,000 in cash from another developer, Jeff McCloy, who is now mayor of Newcastle.

The money was used in Mr Cornwell's campaign to win the seat of Charlestown. Property developers have been banned from donating to NSW political campaigns since 2009.

The expulsion motion is due to be moved by Greens MP Jamie Parker and may be brought on for debate as early as Tuesday afternoon.

But a government spokesman said on Monday night: "The government believes the ICAC inquiry should be allowed to run its course.”

It is understood the government feels the Greens motion is a stunt and no action should be taken against Mr Cornwell until ICAC hands down its findings, which are due by the end of the year.

However, Mr Parker said it would be "breathtaking if the Liberal Party provided political cover to an MP who has admitted this corrupt and unethical behaviour".

"Failing to expel this MP would condemn the Liberals as a party not only condoning, but actively protecting corrupt behaviour," he said.

Opposition leader John Robertson said Labor would vote in favour of the motion "because of the serious nature of what Mr Cornwell has admitted to".

"I continue to be shocked by what we see playing out at ICAC," Mr Robertson said.

"Despite promising to end the scandal, we continue to see a conga line of Liberals ministers and MPs dragged down to explain themselves."

Independent MP for Sydney, Alex Greenwich, said he would vote to expel Mr Cornwell, but felt Mr Parker should have sought co-sponsors for the motion "to put it above party politics".

"It is important the parliament restores community confidence and makes a united stand against corruption and expels those who have admitted to taking bribes," he said.

Greg Piper, the independent MP for Lake Macquarie, said he would decide how to vote on the motion in due course. But he said it was "untenable for Andrew Cornwell to stay in parliament. One way or another he needs to leave."

Mr Piper said he had been planning to move an expulsion motion against Mr Cornwell and was disappointed the Greens had chosen to "contaminate" the debate by "using it in a party political way".

But Mr Parker said only one member could move for expulsion: "This isn't about parties – it's about the community's faith in parliament".