It is inevitable that police officers' access to firearms will increase, Prime Minister John Key says.

However, he questioned whether it would make them safer, saying individuals would still have to make the call to "take that gun out of their holster and, ultimately, whether they use it".

Mr Key's comments followed Police Commissioner Howard Broad today presenting Police Minister Judith Collins with a draft report on training more police to use firearms and placing more firearms in more police vehicles.

Mr Broad said more police should have access to handguns while on routine patrol but that no decision had been made on exactly which vehicles would carry the guns in lock boxes.

He and Mrs Collins said it was not necessary to arm all police.

But Mr Key said the Government needed to make sure police were safer - something highlighted by the brutal machete attack on Taihape Senior Constable Bruce Mellor at the weekend.

"... there's no question we are making an inevitable move towards more police officers having access to firearms," he said.

"Whether that will actually make them safer, I think the jury's out on that because it's one thing for a police officer to have access to a firearm, it's another issue for them to make the right call about whether they actually take that gun out of there holster and ultimately about whether they use it."

Mr Key said he would be cautious about the wholesale arming of police, "where every police officer in New Zealand walks round with a gun on their hip".

"I don't believe that's a step in the right direction and I think it would fundamentally change the relationship between police and the New Zealand public," he said

"For a start off, it's more intimidating when you see a police officer with a weapon. That's certainly my experience in living overseas, and seeing that kind of environment."

Mr Broad today said he was discussing with the minister issues around double-crewing - pairing up police for routine patrols.

Mrs Collins, who yesterday described as "horrendous" and "utterly sickening" the attack on Mr Mellor, said she would read the report and have further discussions with cabinet colleagues and police officials.

The minister and her commissioner signalled that rural police officers in patrol cars were most likely to receive extra guns.

Police could have guns with them, kept in a box in their vehicle's boot, but Mr Broad had been looking at a policy change where they could be kept within hand reach in the vehicle.

He said today the changes would remove requirements for police to get authorisation and set up cordons before weapons could be used. He wanted guns available in frontline vehicles: cars used for incident patrols, crime and inquiries.

Mrs Collins said the policy change had been in train for some time and was not a "knee-jerk" reaction to the attack on Mr Mellor.

Nine police officers have been shot in the past two years -- two fatally -- and Police Association president Greg O'Connor has called on Mr Broad to authorise every front-line patrol car to carry a Glock pistol in a locked gun safe between the driver and passenger.

Green MP Keith Locke said New Zealand's tradition of a largely unarmed police force should be jealously guarded.

"The Greens favour double-crewing police cars in isolated areas as a better response than providing individual officers guns in locked boxes," he said.

Guns would not necessarily protect officers in rural areas, particularly if criminals armed themselves in response.

- NZPA