Just six days after a white supremacist gunman killed 50 people and injured dozens more at two mosques in the city of Christchurch, New Zealand Prime Minister Jacinda Ardern announced Thursday that the country will ban all military-style semi-automatic weapons, assault rifles, and high-capacity magazines.

"We are announcing action today on behalf of all New Zealanders to strengthen our gun laws and make our country a safer place."

—Jacinda Ardern, New Zealand Prime Minister

"Cabinet agreed to overhaul the law when it met on Monday, 72 hours after the horrific terrorism act in Christchurch. Now... we are announcing a ban on all military-style semi-automatics and assault rifles in New Zealand," Ardern said at a press conference. "Every semi-automatic weapon used in the terrorist attack on Friday will be banned in this country."

"On 15 March, our history changed forever. Now, our laws will, too," she added. "We are announcing action today on behalf of all New Zealanders to strengthen our gun laws and make our country a safer place."

New Zealand PM Jacinda Ardern moves to ban all military style weapons, effective immediately: "Every semi-automatic weapon used in the [Christchurch] terrorist attack will be banned in this country." Via BBC pic.twitter.com/S6xE2vKy0C — Kyle Griffin (@kylegriffin1) March 21, 2019

Ardern's quick and decisive action following the Christchurch attack was praised by progressives in the United States, where even the most modest proposals to change America's gun laws following frequent mass shootings are met with fervid opposition from the Republican Party and the powerful gun lobby.

"This is what real action to stop gun violence looks like," tweeted U.S. Sen. Bernie Sanders (I-Vt.), a 2020 presidential candidate. "We must follow New Zealand's lead, take on the NRA, and ban the sale and distribution of assault weapons in the United States."

Rep. Alexandria Ocasio-Cortez (D-N.Y.) added:

Sandy Hook happened 6 years ago and we can’t even get the Senate to hold a vote on universal background checks w/ #HR8.



Christchurch happened, and within days New Zealand acted to get weapons of war out of the consumer market.



This is what leadership looks like https://t.co/TcdR63anBt SCROLL TO CONTINUE WITH CONTENT Never Miss a Beat. Get our best delivered to your inbox.





— Alexandria Ocasio-Cortez (@AOC) March 21, 2019

New Zealand's new reforms—which are supported by the leader of the country's opposition National Party—will officially take effect in three weeks, and interim measures are expected to stop a flood of assault rifle purchases in the meantime.

"I can assure you that'd be a fairly pointless exercise," Ardern said of attempts to buy assault weapons before the new legislation takes effect.

As for assault rifles and semi-automatic weapons already in circulation, Ardern announced a gun buyback program that resembles the plan Australia implemented following the Port Arthur massacre in 1996.

In addition to taking the lead on bold gun law reforms, Ardern issued a "global call" to fight white nationalism in the aftermath of last week's terrorist attack, which appears to have been motivated by Islamophobic ideas and rhetoric.

Addressing other world leaders in an interview this week, Ardern said white nationalism must be confronted "where it exists," and nations must make sure they "never create an environment where it can flourish."

"If we want to make sure globally that we are a safe and tolerant and inclusive world, we cannot think about this in terms of boundaries," she said.