New Zealand will ban all types of semi-automatic weapons used in the Christchurch attacks, PM Jacinda Ardern has said.
The country's gun laws have been in the spotlight since a gunman killed 50 people at two mosques last Friday.
Ms Ardern said she expected new legislation to be in place by 11 April.
She said a buy-back scheme would be set up for banned weapons, and that measures would be imposed to prevent a run on buying before the law comes in.
"Now, six days after this attack, we are announcing a ban on all military style semi-automatics (MSSA) and assault rifles in New Zealand," the prime minister said.
"Related parts used to convert these guns into MSSAs are also being banned, along with all high-capacity magazines."
Victims of the Christchurch shootings
Addressing the impact on gun-owners, the PM said there would be some limited exemptions for New Zealand's farmers.
"We have also acknowledged that some guns serve legitimate purposes in our farming communities, and have therefore set out exemptions for 0.22 calibre rifles and shotguns commonly used for duck hunting," she said.
Ms Ardern said officials had estimated that the buyback could cost "anywhere between $100m ($69m; £52m) and $200m. But that is the price that we must pay to ensure the safety of our communities."
"I strongly believe that the vast majority of legitimate gun owners in New Zealand will understand that these moves are in the national interest, and will take these changes in their stride," she said.
"When Australia undertook similar reforms, their approach was to allow for exemptions for farmers upon application, including for pest control and animal welfare. We have taken similar action to identify the weapons legitimately required in those areas, and preclude them."
New Zealand's police minister Stuart Nash said of the development: "I want to remind that it is a privilege and not a right to own a firearm in New Zealand."