Two US senators have reached a compromise to be announced Wednesday that would expand background checks for gun sales, an official said, in what could result in the most ambitious change to gun laws since 1994.
The deal comes four months after the Connecticut elementary school massacre that took the epidemic of gun violence in the United States to an alarming new level. Twenty small kids were slaughtered by young and deranged shooter, as were six staffers.
Democrat Joe Manchin, backed by veteran Senator Chuck Schumer, forged an agreement with Republican Pat Toomey that is expected to see the background checks expanded to all commercial sales, including those made at gun shows and on the Internet.
A Senate aide confirmed the deal to AFP, and details of the plan will be unveiled at an 11:00 am (1500 GMT) press conference.
Any Republican support for Democratic-led gun-safety legislation will be crucial for the measures to pass Congress, especially the Republican-led House of Representatives.
The Senate Democratic leadership has already introduced three-part legislation that would require expanding background checks to virtually all gun sales, make gun-trafficking a felony, and boost funding for school safety.
Majority Leader Harry Reid has scheduled a showdown vote on the measure for Thursday.
He has also said he would allow lawmakers from both parties to introduce amendments to the overarching legislation, and the Manchin-Toomey compromise would likely be introduced as such an amendment.
"We really are getting there," Manchin told reporters Tuesday night, adding that by Wednesday "we hope to be at a point to where we can finalize everything."
The compromise would be more strict than current law, which only requires checks when guns are purchased through a licensed dealer.
But it stops short of the universal background checks that President Barack Obama sought in the aftermath of the school massacre in Newtown, Connecticut last December that left 20 children and six adult educators dead.
The text would reportedly close the so-called gun show loophole, which has allowed millions of Americans to purchase weapons at any one of thousands of such commercial events without criminal or mental health background checks.
Currently such checks are only required at licensed dealers. Gun shows, informal sales via the Internet or person-to-person sales have been exempt, except in a few states which have enacted their own legislation.
The compromise is not expected to affect firearm transfers between friends or a family.
Expanded background checks enjoys sweeping public support, with polls showing about nine in 10 Americans in favor. Members of the National Rifle Association, the country's largest pro-gun lobby, are also in favor, although the NRA leadership is against expanding the checks.