In a statement to Fairfax Media after returning from India on Thursday morning, a spokesman for Mr Baird said he was proud of the crackdown on alcohol-fuelled violence and "does not intend to reverse or water down the lockout laws". But it leaves open the prospect the government will consider expanding or weakening the laws if crime data indicates it is required.

Mr Baird's declaration came in response to fears that the laws, introduced in central Sydney and Kings Cross last February, would be weakened after Mr Grant announced a review eight months earlier than planned, and said the regime may change.

Asked whether Mr Baird's commitment extended to the June review or beyond, the spokesman said "the Premier has no intention of changing the lockout laws".

The laws require licensed premises to lock out patrons from 1.30am and stop serving alcohol at 3am. They were introduced after a public outcry over the one-punch deaths of Thomas Kelly and Daniel Christie.

Licensed businesses said the measures had cruelled trade. Doctors and police said they had led to a marked drop in booze-fuelled assaults.

The NSW Police Association and health groups wrote to Mr Baird last week, saying they had learnt the government may be considering scrapping lockouts, and urging him against the move.

A two-year review of the laws was due in February 2016. However, during Mr Baird's absence on Monday, acting Premier and Nationals leader Mr Grant said the government would conduct an earlier review in June, incorporating one-year crime data.

At the time, a senior government source said this could involve tightening or loosening the laws.

Mr Grant, who is also the hospitality minister, said on radio the following day that laws failing to "meet the mark" would be subject to change, adding "[people] want us to be a responsive government … why would you sit on information for 12 months if you learn something earlier?"

On Thursday, a spokeswoman for Mr Grant said since becoming minister in April last year, he had believed the government would review the laws after one year.

However, in October last year, Mr Grant told parliament that a review after two years was "appropriate" because the "full impacts of behaviour change will take time to manifest".

The spokeswoman pointed to a parliamentary committee, dominated by government MPs, that recommended in November the laws should be reviewed "at the earliest possible stage". It said the review should be independent.

She said the government review will be completed in September, and the results released in December.

Foundation for Alcohol Research and Education chief executive Michael Thorn welcomed Mr Baird's commitment to the laws, saying "we can't let the complaints of a few in the liquor industry drive public policy".

Kings Cross Liquor Accord chief executive Doug Grand said if evidence showed lockouts were not effective, the accord expected "adjustments to be made accordingly, at that time."