Tighter gun control is overwhelmingly popular with Americans, and championed by Biden's Democrats, but Republicans have long stood against what a minority view as any infringement on their right to bear arms.
US President Joe Biden has called for a ban on assault weapons and tighter gun control measures as he stepped into the familiar role of grief counsellor for a traumatised nation after a mass shooting left 10 people dead in Colorado.
"I don't need to wait another minute, let alone another hour, to take common sense steps that will save lives in the future," Biden said on Tuesday, adding that "we can ban assault weapons."
"This is not and should not be a partisan issue," Biden said at the White House. "It's an American issue that will save lives, American lives. We must act."
"We can ban assault weapons and high capacity magazines in this country once again," said Biden, recalling that Congress previously overcame its divisions to pass a 10-year ban on assault weapons back in 1994.
"I got that done when I was a senator. It passed," said Biden, who was chairman of the Senate Judiciary Committee at the time. "It was a law for the longest time. And it brought down these mass killings. We should do it again."
Biden spoke before leaving Washington for Columbus, Ohio, a visit where he will mark the 11th anniversary of the signing of the Affordable Care Act known as Obamacare.
Another mass shooting has shaken the US, this time in Boulder, Colorado, where a gunman opened fire in a grocery store, killing at least ten people pic.twitter.com/u6U8oWfPmd— TRT World (@trtworld) March 23, 2021
Second mass shooting
The mass shooting in Boulder followed a gunman's killing the previous week of eight people at spas in Atlanta, bringing new attention to US gun violence.
Flags at the White House were at half staff until sunset on Monday to commemorate the Atlanta shooting victims. They flew at full staff for a few hours on Tuesday morning before being lowered again to mark the Boulder killings.
This month the House of Representatives passed two measures aimed at enhancing background checks and closing a loophole related to a deadly 2015 church shooting in Charleston.
The bills address a hugely popular premise among American voters: that background checks should be required for all US firearm sales, including those at gun shows.
"That's one of the best tools we have right now to prevent gun violence," Biden said of the legislation.
"The Senate should immediately pass, let me say it again: The United States Senate, I hope some are listening, should immediately pass the two House-passed bills that close loopholes in the background check system."
Biden, whose personal life has been marked by the loss of his first wife, and two children, offered his condolences to the families of victims, saying he and his wife, Jill Biden, were devastated by the deaths.
Biden has in recent weeks promoted the coronavirus stimulus bill while grappling with a surge of migrants along the US southern border with Mexico.
Now his two-month-old administration faces increased pressure to fulfil promises on gun regulation.
Any effort to move the United States toward greater gun control has historically been difficult with his fellow Democrats in favour and Republicans largely opposed.
Healthcare for all
Biden will visit Ohio State University's James Cancer Hospital to mark the healthcare bill anniversary and promote a $100 million grant the hospital received under the Affordable Care Act to upgrade its radiation oncology department, according to White House officials.
The Affordable Care Act (ACA), the signature 2010 legislative achievement of then-president Barack Obama, a Democrat under whom Biden served as vice president, has survived repeated attacks from Republicans, on Capitol Hill and in the courts. It is expanding under Biden's watch.
The federal exchange reopened in mid-February for a special enrolment period, with more than 206,000 people signing up for coverage in the first two weeks, nearly triple the number during the same time frame last year, when access was limited to life-changing events, federal data shows.
There are about 28 million Americans without health insurance, down from about 46.5 million in 2010, when the ACA was passed, according to the latest federal figures.