President Joe Biden on Saturday signed the most sweeping gun violence bill in decades, a bipartisan compromise that seemed unimaginable until a recent series of mass shootings, including the massacre of 19 students and two teachers at a Texas elementary school.

“Lives will be saved,” he said at the White House. Citing the families of shooting victims, the president said, “Their message to us was to do something. Well today, we did.”

The House gave final approval Friday, following Senate passage Thursday, and Biden acted just before leaving Washington for two summits in Europe.

The legislation will toughen background checks for the youngest gun buyers, keep firearms from more domestic violence offenders and help states put in place red flag laws that make it easier for authorities to take weapons from people adjudged to be dangerous.

Most of its $13 billion cost will help bolster mental health programs and aid schools, which have been targeted in Newtown, Connecticut, and Parkland, Florida, and elsewhere in mass shootings.

While the bill does not included tougher restrictions that Democrats have long championed, such as a ban on assault-type weapons and background checks for all gun transactions, it is the most impactful firearms violence measure from Congress since enacting a now-expired assault weapons ban in 1993.

“While this bill doesn’t do everything I want, it does include actions I’ve long called for that will save lives,” Biden said.

After years of clashes in Congress over gun rights between Democrats and Republicans, and after countless mass shootings – including those in Newtown, Conn., Parkland, Fla., El Paso, Texas, Orlando, Fla., and Las Vegas – members of both parties banded together to forge a compromise in the wake of last month’s rampages in Texas and New York.

"Tonight, after 28 years of inaction, bipartisan members of Congress came together to heed the call of families across the country and passed legislation to address the scourge of gun violence in our communities," President Joe Biden said in a statement Thursday night after the bill's passage. "Families in Uvalde and Buffalo –  and too many tragic shootings before - have demanded action. And tonight, we acted."

"This bipartisan legislation will help protect Americans," the president continued. "Kids in schools and communities will be safer because of it."

Led by Texas Sen. John Cornyn, a Republican, and Connecticut Sen. Chris Murphy, a Democrat, bipartisan talks on the legislation began in the aftermath of the deadly massacres last month and quickly gained steam in the weeks that followed, culminating in the release of a framework in mid-June backed by 10 Democrats and 10 Republicans – enough to overcome the Senate's filibuster threshold, which had frequently derailed gun rights legislation in the past.

Murphy, a longtime gun advocate who previously represented Newtown, Conn., the site of the 2012 Sandy Hook Elementary School massacre, in the House, and Cornyn, who was tapped by Senate Minority Leader Mitch McConnell, R-Ky., in the wake of the Uvalde shooting, were joined by Sens. Kyrsten Sinema, D-Ariz., and Thom Tillis, R-N.Y., in forging a bipartisan compromise on the legislation.

“This will become the most significant piece of anti-gun-violence legislation Congress has passed in three decades,” Murphy said on the Senate floor ahead of the vote. “This bill also has the chance to prove to the weary American public that democracy is not so broken, that it is able to rise to the moment.”

“I don’t believe in doing nothing in the face of what we’ve seen in Uvalde and other communities," Cornyn said. "Doing nothing is an abdication of our responsibility."

The final vote on the measure was 65-33, with 15 Republicans joining the unanimous Democratic caucus in passing the incremental, yet significant legislation. The bill marks the first federal gun reform legislation in nearly 30 years.

The 80-page, $13 billion bill, known as the Bipartisan Safer Communities Act, includes:

• Enhanced background checks for gun buyers aged 18 and 21
• Closing the so-called "boyfriend loophole," which would extend a ban on those convicted of domestic abuse from buying guns to dating partners who are not living with the victim
• Funding to allow states to set up red flag laws, restrictions which allow police, family members or other individuals to seek a court order to allow authorities to remove firearms from those considered to be a danger to themself or others
• Imposing tougher restrictions on straw purchases and gun trafficking
• Funding for school safety and mental health programs

While the bill falls short of what many gun safety advocates and Democrats have asked for – including a ban on military-style assault weapons and high-capacity ammunition magazines and enacting universal background checks – firearm reform backers cheered the move as a step in the right direction.

“This is not a cure-all for the all the ways gun violence affects our nation,” Senate Majority Leader Chuck Schumer, D-N.Y., said. “But it is a long overdue step in the right direction. It’s significant, it’s going to save lives.”

McConnell, R-Ky., who supported the bill, called it "a package of commonsense and popular solutions to make these horrific incidents less likely."

The Republican lawmakers who voted with Democrats were: Sens. Roy Blunt, R-Mo., Richard Burr, R-N.C., Shelley Moore Capito, R-W.Va., Bill Cassidy, R-La., Susan Collins, R-Maine, John Cornyn, R-Texas, Joni Ernst, R-Iowa, Lindsey Graham, R-S.C., Mitch McConnell, R-Ky., Lisa Murkowski, R-Alaska, Rob Portman, R-Ohio, Mitt Romney, R-Utah, Thom Tillis, R-N.C., Pat, Toomey, R-Pa., and Todd Young, R-Ind.

The House vote was also bipartisan, albeit less so: just 14 Republicans joinedall Democrats in supporting the measure.

One surprising Republican vote was Wyoming Rep. Liz Cheney, who said in a statement: "As a mother and a constitutional conservative, I'm proud to support this sensible bill that will protect our children and limit violence without infringing on law-abiding citizens' Second Amendment rights."

Another Republican who joined Cheney was her fellow member of the House Jan. 6 panel, Illinois Rep. Adam Kinzinger, who is not seeking re-election in November.

A number of House Republicans, including Rep. Tony Gonzales, a lawmaker from Uvalde, Texas, and New York Rep. John Katko, had previously expressed that they will break ranks to support the bill.

In an emotional Twitter post, Gonzales, describing himself as a "survivor of domestic abuse," wrote that he looked forward to voting for the bill: "As a Congressman it’s my duty to pass laws that never infringe on the Constitution while protecting the lives of the innocent."

The vote came just hours after the Supreme Court’s conservative majority struck down a New York concealed carry restriction, greatly expanding the rights of Americans to carry firearms in public, marking a mixed day for gun safety reform advocates.