Police Minister Stuart Nash says a ban on semi-automatic weapons is just the first step with a review into a number of other changes, including a possible gun register, still to come. 

Yesterday, Prime Minister Jacinda Ardern announced Military-style semi-automatics and assault rifles will be banned under stronger new gun laws.

The country's rules around guns have been in the spotlight since last Friday's mosque shootings in Christchurch, which killed 50 people. 

Speaking with Mike Hosking, Stuart Nash said banning semi-automatic weapons is the right move.

"The important first step is getting these guns, these are the guns that a terrorist used to kill 50 Kiwis, getting them out of the market once and for all."

He said they will be reviewing other areas of gun law including things like registers, ammunition types and the licensing process. 

"There are two or three phases to this. The first one is banning these weapons and getting them out of the market."

"The second phase is looking at things in a little more detail, like a register, like the type of ammunition, and how people get  licenses."

When asked whether he favoured a gun registration, Nash said he needed to know more about it first.

"There is a paper that is going to go before Cabinet on Monday that talks about this and so I need to better understand what the implications of this are."

"I certainly favour more oversight into what is happening."

The Police Minister reiterated that they haven't made any decisions on a gun register yet. He said the main focus right now is getting semi-automatic weapons out of the market.

"You will no longer be able to buy a military-style semi-automatic weapon that was basically designed to kill people."

"The AR-15, that the terrorist used to kill 50 people, is the civilian version of the M16 which the ground troops used in Vietnam."

"The guns that this terrorist used to kill people will be illegal by 11 April."