The US House of Representatives, spurred by a series of mass shootings, passed a bill on Friday that would ban assault weapons for the first time in decades.
The legislation was approved by a 217 to 213 vote in the Democratic-majority House and now goes to the Senate, where it is likely to be rejected.
Gun reform is a divisive issue in the US despite deadly mass shootings, with only two Republicans joining Democrats to back the assault weapons ban in the House.
“When guns are the No 1 killer of children in America, when more children die from guns than active-duty police and active-duty military combined, we have to act,” President Joe Biden said in a statement.
In the 100-member Senate, Democrats have 50 seats, and 10 Republican votes are needed to bring a measure to the floor for consideration.
Congress passed a 10-year ban on assault rifles and certain high-capacity magazines in 1994, but it was allowed to expire in 2004 and sales of the weapons have soared since then.
“The majority of the American people agree with this common sense action,” Mr Biden said. “The Senate should move quickly to get this bill to my desk, and I will not stop fighting until it does.
Democratic House Speaker Nancy Pelosi called the latest bill a “crucial step in our continuing fight against the deadly epidemic of gun violence in our nation”.
It would ban the sale, import, manufacture or transfer of certain semi-automatic weapons such as those used in recent mass shootings in Buffalo, New York, Uvalde, Texas, and Highland Park, Illinois.
An avowed white supremacist shot dead 10 African Americans at a supermarket in Buffalo in May.
Nineteen schoolchildren and two teachers were killed by an 18-year-old man at an elementary school in Uvalde that same month and seven people were shot dead at a July 4 parade in Highland Park.
After the Uvalde massacre, Mr Biden appealed to politicians to again ban assault rifles or at least raise the minimum age for buying them from 18 to 21.
But Republicans, who see such a restriction as contrary to the constitutional right to bear arms, have refused to go along.
A school shooting in 2012 in Newtown, Connecticut, left 20 children and six school employees dead.
On Friday, the parent company of far-right conspiracy website InfoWars filed for US bankruptcy protection as the company and its founder Alex Jones face up to $150 million in damages in a trial over false claims that the massacre was faked.
Agence France-Presse contributed to this report