Top Democratic leaders pushed President Trump and Senate Republicans on Monday to take swift action on gun legislation at their first appearance at the end of a congressional recess, seeking to channel public frustration into action after another series of mass shootings.

House Speaker Nancy Pelosi (D-Calif.) and Senate Minority Leader Charles E. Schumer (D-N.Y.) focused their attention at a Capitol Hill news conference on legislation, already passed in the House, that would expand the federal background check system to cover more gun sales, including those between private individuals rather than a gun dealer.

“The legislation is the quickest way to make a law that will save American lives,” Schumer said. “It’s right at the intersection of what is really effective and what can pass.”

Pelosi and Schumer were joined by other leaders who saw their communities affected by the recent mass shootings — Rep. Veronica Escobar (D-Tex.), who represents El Paso; Nan Whaley, the Democratic mayor of Dayton, Ohio; and Sen. Sherrod Brown (D-Ohio).

All three said they were frustrated with inaction on the gun issue in the face of public demands for a response — and in some cases, overwhelming public support for some of the legislation they are proposing.

A Washington Post-ABC News poll released Monday finds overwhelming support across partisan and ideological lines for the expansion of background checks, as well as the establishment of “red flag” laws allowing law enforcement, at a judge’s discretion, to temporarily seize guns from troubled individuals. More than 80 percent of Americans support each policy.

“What I kept hearing over and over and over again from El Pasoans was, why?” Escobar said, recounting conversations she has had since a gunman left 22 people dead in a Walmart there Aug. 3. “I’ve had constituents ask me what it’s going to take for Mitch McConnell to see the blood that we saw spilled in our community and to feel the torturous pain that we have felt . . . and it is a very difficult question to answer.”

Whaley said that before embarking for Washington, she had gotten a text message from the mother of Monica Brickhouse, a victim of the Aug. 4 shooting in her city that left nine dead. The mom’s message: “Go get ’em.”

“They want us to do something, and so that’s why I’m here,” Whaley said. “I don’t know anything else that 9 out of 10 Americans agree on.”

McConnell did not address gun legislation Monday in his first remarks on the Senate floor, instead discussing government funding and presidential nominations.

The top Republicans in the House and Senate are scheduled to meet with Trump at the White House on Tuesday, with senators suggesting that various fall agenda issues such as government spending, trade and guns would be discussed.

Sen. John Cornyn (R-Tex.) said White House officials involved in negotiations with lawmakers are expected to present some options on guns to Trump later this week. Republicans said they have one message for the president.

“You’ve got to tell us what you’re for, you know, I think that’s what all our members are going to be saying. Because this is, as you know, it’s an issue that is a very challenging one for a lot of our members,” said Sen. John Thune (S.D.), the No. 2 Senate Republican.

In an interview with radio host Hugh Hewitt last week, McConnell said he is looking to Trump to weigh in first before endorsing any legislation responding to the violence.

“If the president is in favor . . . and I know that if we pass it, it’ll become law,” he said, “I’ll put it on the floor.”

McConnell has embraced an epithet frequently used by his political opponents, the “Grim Reaper,” referring to his determination to sideline left-leaning legislation passed by the House and supported by Democrats. But in this case, the polling indicates, it might not be only Democratic voters McConnell is alienating.

Trump, meanwhile, has yet to solidly endorse any response to the string of shootings — which, besides the El Paso and Dayton tragedies, include mass killings in Gilroy, Calif., on July 28, and Midland and Odessa, Tex., on Aug. 31. He has promised to deliver a package of proposals but has offered no firm timeline for doing so.

The president has publicly played down the potential for the expansion of background checks, explaining that he would rather focus any legislation on those with mental illnesses.

Pelosi and Schumer said Monday that would not be sufficient, calling universal background checks a necessary precursor to any further legislation aimed at addressing the spate of tragedies.

The House Judiciary Committee on Tuesday is set to advance other gun-related bills — including legislation encouraging states to pass red-flag laws and a ban on high-capacity ammunition magazines — but support for those bills tends to be more partisan. Top party leaders have instead kept the focus on background checks, hoping to overcome opposition from the National Rifle Association and other gun-rights groups that say it would be an infringement of the Second Amendment to require private sellers to seek federal screening for their buyers.

“We are once again asking the Grim Reaper, informing the Grim Reaper, that these bills are alive and well in the public — that public opinion, public sentiment will weigh in,” Pelosi said. “We will make this issue too hot for him to handle.”

But there were indications Monday that any hope of bipartisan compromise — essential in a divided Congress — might be fleeting. One Democratic senator who had been engaged with the White House in negotiating possible gun legislation — and expressed a degree of optimism about those talks late last month — issued a pessimistic statement Monday.

Sen. Chris Murphy (D-Conn.) said he was “still negotiating in good faith” to expand background checks to more gun transactions. “But as each day goes by, it seems more likely that we’re going to find ourselves back in a familiar place where 90 percent of the Americans who want more background checks are going to be disappointed once again,” he said.

Paul Kane contributed to this report.