When NSW police officers are next faced with a terrorist incident, they'll be in no doubt they have the legal authority to shoot to kill and, by the end of the year, more will be armed with high-powered weapons.

The state government will introduce legislation within a fortnight to give the police commissioner the ability to declare a terrorist incident which will allow officers to fire as required.

At present, officers tasked with taking a so-called kill shot must believe their target poses an imminent threat to another person before they can fire their weapon.

"At the moment they have to determine, in their own mind, if they have the legal ability to use lethal force," Commissioner Mick Fuller told reporters on Thursday.

"It's impossible to make that decision with any certainty and, if there is uncertainty, you can understand an officer will hesitate."

The NSW coroner who investigated the 2014 Lindt Cafe siege found snipers had a 10-minute window during which they could have taken a kill shot at Man Haron Monis but they weren't sure of their legal justification to use lethal force.

Michael Barnes recommended the government consider amended police power laws to ensure officers "have sufficient legal protection to respond to terrorist incidents".

The NSW and federal government on Thursday said they accepted all of the coroner's 45 recommendations relevant to their respective jurisdictions.

The state government also vowed public order and riot squad officers would have access to rapid-fire high-powered rifles by the end of the year.

At present, only the tactical operations unit (TOU) and their regional counterparts carry long-arm weapons.

Mr Fuller said the expanded roll out would double the capability of the NSW Police in terms of the long arms response to an incident.

"It also gives us a greater capacity to support TOU if there's a siege or an incident. There is a second layer of response before you get to general duties."

The commissioner said riot squad officers wouldn't always carry the weapons in public but they'd always be close at hand.

Monis was shot by specialist police who stormed the Lindt Cafe some 17 hours after he walked into the building with a shotgun and took 18 people hostage.

The terrorist was free on bail at the time despite facing 40 serious charges for sex offences and accessory to the murder of his estranged wife.

A tightening of parole laws, originally slated for later in the year, have been brought forward as part of the government's package.

Inmates linked to terrorism, or radicalised while in prison, may find their parole denied by the State Parole Authority, Premier Gladys Berejiklian said.

The parole board will be able to refuse parole even if an inmate wasn't jailed for a terror-related offence.

NSW Labor will support the government's legislation.

Federal Attorney-General George Brandis on Thursday announced the Commonwealth was accepting the 12 Lindt inquest recommendations relevant to it, including working with the states to strengthen information sharing on criminal history and the use of the military in terrorist incidents.