Premier Gladys Berejiklian has announced NSW Police Commissioner Andrew Scipione will be retiring in April — a couple of months earlier than expected.

The announcement timing has left many scratching their heads, with no replacement in sight and only two months to go.

Mr Scipione had extended his term as police chief at the request of former Premier Mike Baird, and it was expected he would stay until July 2017.

The Premier and Police Minister Troy Grant were questioned over the timing of the announcement and whether there would be enough time to find the right replacement.

"We've already started the process of recruiting his successor," said Ms Berejiklian, indicating that in her first Cabinet meeting as leader it was agreed they would advertise the position.

This leaves only two months for a replacement to be found, with the Premier saying they were looking locally.

"If other people put their hand up we will consider them, but our recruitment focus will be on New South Wales and Australia."

Recruitment mired by siege and police bugging

Deciding on Mr Scipione's replacement has been a fraught issue for the Government, as explosive revelations from the police bugging scandal marred the reputations of two of his potential replacements, Deputy Commissioner Catherine Burn and former Deputy Commissioner Nick Kaldas.

Mr Scipione has dismissed suggestions the Premier asked him to finish up early, saying it was always his intention to leave in April.

"I advised the former Premier of this last year," the Commissioner said.

In December an ombudsman's inquiry into the police bugging scandal found Ms Burn engaged in unlawful conduct and Mr Kaldas may have given misleading evidence.

Ms Burn's actions were also under the spotlight during the inquest into the Sydney siege.

In August, the State Opposition and an alliance of crossbenchers joined forces to demand the Government replace Mr Scipione with Mr Kaldas, who has taken up an overseas position.

On the same day, the State Government announced a once-in-a-generation restructure of NSW Police aimed at future proofing the force and appointing a successor for when Mr Scipione retired.

The bad blood between Mr Kaldas and Ms Burn divided the police force, with Mr Scipione revealing during a budget estimates hearing that he had hired external consultants to try to unite senior ranks of the force torn apart by the police scandal.

The Premier would not be drawn on who she would like to replace Mr Scipione.

"I will not speculate on personalities but what I will say is we have put a robust process forward," she said.

When asked if she was close to former deputy commissioner Nick Kaldas, Ms Berejiklian did not answer the question.

'Bravery in dark days'

The Premier praised Mr Scipione especially his "courage and bravery during some very dark days".

The police chief said he was proud that police statistics reflected a reduction in crime across the board.

"There are people that are walking around our streets today that did not become victims of crime. They weren't raped, they weren't the subject of an assault, they didn't have their car stolen or their house broken into," Mr Scipione said.

"We made sure we did all we could to stop people becoming victims of crime."

But Greens MP and the party's police spokesman David Shoebridge has criticised the Government over the time it has taken to find Mr Scipione's replacement.

"It is remarkable despite the Government knowing a replacement was needed for over two years, Cabinet has been unable to agree on Commissioner Scipione's replacement." he said.

"Commissioner Scipione's contract extension was always a stop gap measure and it came at the cost of a $100,000 per annum salary increase to NSW taxpayers."

Mr Scipione's last day will be April 2. The Premier said the new police commissioner would start on the job that day.