Top Democratic congressional leaders set aside a brewing showdown over presidential oversight Monday and pitched President Trump on a “big and bold” infrastructure bill ahead of a White House meeting on the issue, insisting there are “significant majorities in both the House and Senate” ready to act.

House Speaker Nancy Pelosi (D-Calif.) and Senate Minority Leader Charles E. Schumer (D-N.Y.) are set to meet Trump on Tuesday, joined by other leading Democrats. In a letter sent Monday, the pair asked Trump to entertain infrastructure legislation with “substantial, new and real revenue” — as opposed to previous GOP plans that have focused on using smaller amounts of public money to leverage private investments. They did not specify a dollar figure for the package, though many Democrats have discussed $1 trillion as a bare minimum.

Paying for that sort of investment is the major challenge, and potential revenue sources all carry political risks. Lawmakers from both parties have discussed potentially increasing the federal gas tax for the first time since 1993, but Democrats are more keenly eyeing a rollback of the Republican tax cuts that Trump signed into law in 2017.

A Democratic official close to Schumer said the Senate leader would not consider a gas tax hike — which would be a disproportionate burden on working-class voters — unless Republicans consider undoing some of their tax cuts for corporations and wealthy Americans. The official spoke on the condition of anonymity to be candid about internal deliberations.

“We look forward to hearing your ideas on how to pay for this package to ensure that it is big and bold enough to meet our country’s needs,” the leaders wrote to Trump Monday.

Pelosi and Schumer also said any infrastructure bill must address “clean energy and resiliency priorities” and expand “beyond transportation and into broadband, water, energy, schools, housing and other initiatives.” They also call for “strong Buy America, labor, and women, veteran and minority-owned business protections” — provisions important to key players in the Democratic coalition.

The Democratic leaders’ emphasis on bipartisanship comes at a time when relations between the White House and congressional Democrats could hardly be worse, with Trump determined to resist virtually every effort on Capitol Hill to investigate and check his administration. For instance, Attorney General William P. Barr’s scheduled testimony this week before the House Judiciary Committee is in question amid a dispute over the format of the hearing.

But Pelosi and Schumer have insisted on making legislative entreaties to Trump — particularly on the issues of infrastructure and prescription drug pricing, where they see a path to a bipartisan deal. They believe Democrats have to show progress, or at least a good-faith effort, on their kitchen-table campaign promises of growing paychecks, shoring up health care and otherwise improving middle-class life.

“Democrats are able to do two things at once,” said Rep. David N. Cicilline (D-R.I.), chairman of the party communications committee. “We are going to aggressively demand that the administration officials we have sought testimony from come before Congress. . . . At the same time, we’re going to continue to move forward on the agenda we ran on for the people of this country. We have the responsibility to do both things and we’ll do them both vigorously.”

Regarding infrastructure, Pelosi and Schumer wrote Monday: “This bipartisanship is a reflection of the American people’s recognition of the need to rebuild our infrastructure to promote commerce, create jobs, advance public health with clean air and clean water, and make our transportation systems safer — indeed, to improve the quality of life of all Americans.”

But it remains to be seen what common ground, if any, can be found. Reversing any part of the 2017 tax law could be a red line for Trump and congressional Republicans, who consider the Tax Cuts and Jobs Act the crowning legislative accomplishment of the administration. Undoing the cuts, some fear, could undermine a strong economy.

Democrats, meanwhile, see that revenue as crucial to any deal, and any Republican willingness to engage in that conversation stands to be an early indicator of whether Tuesday’s talks are fruitful.

The outline of the meeting is so unclear that Democrats do not know whether Trump will bring in the White House press corps the way he did for an infamous December meeting with Schumer and Pelosi just before the 35-day partial shutdown of agencies, a public exchange with Trump that Democrats believe set the stage for them to win the shutdown fight.

“Didn’t work out so badly last time,” Schumer said of the previous televised exchange.

But others hoped for a more substantive talk not carried live on cable TV. “I hope not,” House Majority Leader Steny H. Hoyer (D-Md.) said exiting a more than hour-long huddle prepping for Tuesday’s Trump meeting. “That doesn’t lead to productive discussions.”

White House officials on Monday played down the prospect of a breakthrough at the meeting.

National Economic Council Director Larry Kudlow told reporters Monday the meeting would be “a good sit-down, a good discussion,” but the administration would not be pitching Democrats on any specific infrastructure proposal.

Press secretary Sarah Sanders suggested the meeting could touch on topics far afield from infrastructure.

“Look, the primary purpose of that meeting is to discuss infrastructure, but I certainly wouldn’t be surprised at all if immigration comes up,” she said Monday on Fox News. “It’s a major problem in this country, and so far Democrats have refused to acknowledge it and address it.”

The House Democrats joining Pelosi at the meeting include Majority Leader Steny H. Hoyer (Md.), Majority Whip James E. Clyburn (S.C.) and Assistant Speaker Ben Ray Luján (N.M.), as well as Transportation and Infrastructure Committee Chairman Peter A. DeFazio (Ore.) and Ways and Means Committee Chairman Richard E. Neal (Mass.).

The Senate Democrats set to join Schumer are Minority Whip Richard J. Durbin (Ill.); Assistant Minority Leader Patty Murray (Wash.); Democratic Policy and Communications Committee Chair Debbie Stabenow (Mich.); Sen. Thomas R. Carper (Del.), the top Democrat on the Environment and Public Works Committee; and Sen. Ron Wyden (Ore.), the top Democrat on the Finance Committee.

Seung Min Kim, John Wagner and Paul Kane contributed to this report.