Washington: US President Donald Trump has signed an order to ban bump-stock devices or modified guns that enables one to shoot hundreds of rounds per minute and was used by a gunman to kill 58 Las Vegas concert-goers in 2017.
Speaking at the White House on Tuesday, Trump said he has directed the Justice Department to propose a law to make the accessories illegal, the BBC reported.
He said he directed Attorney General Jeff Sessions to finalise new guidelines to declare bump stocks illegal "very soon".
The gun control debate took on a new urgency after 17 young students were killed at a school in Florida last week.
Trump said: "We cannot merely take actions that make us feel like we are making a difference, we must actually make a difference."
Stressing focus on evidence-based solutions and security measures that would actually work, Trump said that the new rules were aimed at making "it easier for men and women of law enforcement to protect our children..."
With the help of bumped devices semi-automatic rifles work as machine guns. They can be bought for as little as $100 without the need for a criminal background check.
One of these was used by 64-year-old gambler Stephen Paddock to rain bullets on a Las Vegas crowd in October 2017. It was America's worst ever mass-shooting by a lone gunman that injured more than 500 people also.
Both Democrats and Republicans agreed in the nationwide wave of horror following the Las Vegas attack that the sale of bump stocks should be outlawed.
But a bill introduced to ban bump stocks, trigger cranks and other devices that can speed up a semi-automatic rifle's rate of fire has since stalled.
Students and parents affected by the massacre at the Marjory Stoneman Douglas High School last week have set out on a demonstration in the state capital of Tallahassee on Wednesday.
Hundreds of students were on their way to the state capital to lobby their lawmakers over the national issue, the BBC said.
"We're travelling to our state capital to make sure that none of these people that we grew up with - that we've known our whole lives - die in vain," Julia Salomone, 18, said.