The US House of Representatives passed a gun control bill on Wednesday that would raise the minimum age to 21 from 18 on purchases of certain firearms and toughen prohibitions on untraceable guns.
The bill, which passed 223 to 204, is highly unlikely to pass the Senate where it would require the votes of 10 Republicans.
Rather than pushing for a quick vote on the sweeping House bill, Senate Majority Leader Chuck Schumer has opted to give more time for the bipartisan negotiations.
The Senate negotiations, led by Democrat Chris Murphy and Republican John Cornyn, are also including measures such as upgrades to school security, strengthening mental health services and doing more to keep guns out of the hands of people who are legally barred from owning them, such as felons.
Democrats in the past have tried to pass wide-ranging gun control legislation to stem the tide of mass murders, which already have topped 200 this year alone in the United States, and other gun-related violence.
This time, Democrats have signalled to Republicans that they would be willing to accept a much more narrow first step with legislation, even as President Joe Biden calls for tougher action, such as banning assault weapons.
Wednesday's vote follows a shooting in Uvalde, Texas on May 24, when an 18-year-old shooter killed 19 pupils and two teachers at school.
The shooter was allowed to remain in a classroom at Robb Elementary School for nearly an hour while officers waited in a school hallway and children in class made panicked phone calls for help.
A US Border Patrol-led tactical team ultimately burst into the classroom and killed the gunman.


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