(Bloomberg) -- Attorney General William Barr is circulating a proposal to senators on expanding background checks for firearms purchases, but lawmakers say they still don’t know where President Donald Trump stands.

Senator Pat Toomey, a Pennsylvania Republican and supporter of closing some loopholes in the background check system, said he spoke to Barr about it late Tuesday.

Barr “has developed an idea that has a lot of merit and is a very thoughtful contribution to this whole conversation,” Toomey said. “There are a lot of details that we still need to flesh out. But it’s a very constructive addition.”

Negotiations on potential new firearms restrictions spurred by mass shootings last month in Texas and Ohio have been stymied while Republicans look to the White House for any idea of what the president would sign. Toomey didn’t answer questions about whether the president backs the proposal.

Eric Ueland, the White House’s top lobbyist, said the proposal shouldn’t be seen as an endorsement by Trump for a particular approach but is part of a broader effort to reach out to lawmakers for their ideas.

‘The President’s Call’

“The president has asked us to talk and listen to prospective views, opinions, ideas and concepts from members of Congress and that’s what we continue to do,” Ueland said.

He declined to say who authored the proposal and what type of feedback the administration is getting about it. Asked when Trump will decide what he’ll support, Ueland said, “It’s the president’s call.”

Senator Chris Murphy, a Democratic senator taking part in the negotiations, said he’s aware of the proposal being circulated by Barr and will be speaking with the administration about it Wednesday.

“We’re actively talking with the White House today,” said Murphy of Connecticut. “Talks are ramping up, not ramping down.”

Murphy added that he hasn’t yet determined whether he would support the ideas Barr is circulating, but that it generally reflects elements of 2013 legislation sponsored by Toomey and Democratic Senator Joe Manchin of West Virginia that would extend federal criminal background checks to purchases made on the Internet and at gun shows.

‘Red Flag’ Laws

Trump, who’s been briefed by aides on some of the options being discussed, has publicly stated support for expanded background checks. But he also has shifted his position, most recently expressing doubt about whether they would be effective in curbing gun violence.

He has previously threatened to veto a House bill that would extend background checks to sales between individuals.

Senate Majority Leader Mitch McConnell reiterated Tuesday that he won’t advance any legislation without knowing whether the president would sign it. Other ideas under discussion include legislation encouraging states to adopt “red flag” laws that allow courts to issue protective orders taking firearms from people determined to pose a danger to themselves or others.

To contact the reporter on this story: Laura Litvan in Washington at llitvan@bloomberg.net

To contact the editors responsible for this story: Joe Sobczyk at jsobczyk@bloomberg.net, Laurie Asséo

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