National is pledging to work constructively with the government to implement its just-announced gun law changes.
Prime Minister Jacinda Ardern this afternoon announced a ban on all military-style semi-automatic weapons and all assault rifles.
National Party leader Simon Bridges said he agreed that members of the public did not need access to that type of weapon.
He said he also supported limiting access to other high-powered semi-automatic weapons and ammunition.
"I think now is a time for unity in New Zealand, I think now is the time when we've got to act in the national interest to make sure New Zealanders are safe. That's why we support the prime minister and the government and the changes that are being made."
Green Party co-leader James Shaw also welcomed today's ban but said he wished it was not in such tragic circumstances.
"Banning military style semi-automatic weapons and assault rifles makes everyone safer. Banning these guns is the first step towards systemic changes to our gun laws," Mr Shaw said in a statement.
He said the Greens were working with its government partners on further action to tighten access to guns.
However, ACT leader David Seymour was worried the government was rushing through its gun law changes.
While he supported change in principal, he believed the public and Parliament should have a proper say before anything was made law.
Mr Seymour said he would not pledge his party's support to new laws banning military-style semi-automatic guns and assault rifles until he saw the legislation.
The Police Association was also supporting the weapons ban and praised the government for acting swiftly and decisively.
Its president, Chris Cahill, said the government had demonstrated great courage.
"It's a good mix of reforms that balance the practical requirements of firearm owners in New Zealand with the need to protect society, we're very pleased."
Mr Cahill said the changes were the minimum police officers would expect.
Federated Farmers is also supporting the government's move to toughen up firearms regulations.
Its rural security spokesperson Miles Anderson said in a statement that the move would not be popular amongst of some of its members.
"But a clampdown is the responsible path to take to try to ensure we're never witness to this kind of tragedy on our shores again."
Mr Anderson said he was pleased farmers would still have access to sporting semi-automatic rimfire rifles, such as the .22 long rifle and sporting semi-automatic shotguns with limited magazine capacity which are needed for pest control.
But he said any access to these should be controlled by the kinds of police checks, registration of individual firearms and increased security requirements currently needed for E category licences.