Trump admin updates: Trump says tariff letters to be sent to 'various countries' on Monday

The White House had a message for Republicans on Monday as lawmakers rush to try to pass President Trump's megabill before his July 4 deadline.

"Republicans need to stay tough and unified during the home stretch, and we are counting on them to get the job done," White House press secretary Karoline Leavitt told reporters at her briefing.

Leavitt was asked about the bill's prospects in the House, which will have to sign off on the Senate changes. There is currently little room for error in either chamber for Republicans -- Speaker Mike Johnson can only afford three defections if all members are present and voting.

"We need the full weight of the Republican conference to get behind this bill and we expect them to, and we are confident they will," Leavitt said.

"The president has been working hand in hand with Senate Majority Leader Thune and also our House Republican Leader, or the Speaker of the House Mike Johnson, both of whom will be at the White House today to meet with the president yet again. I believe they were here this morning," she added.

The Senate gaveled in on Monday morning to begin a "vote-a-rama" on amendments proposed to President Trump's "One Big Beautiful Bill Act."

Senate Minority Leader Chuck Schumer, the chamber's top Democrat, said his party "will bring one amendment after the other again and again and again to put Republicans on the record."

"Mr. President, today Senate Republicans have to decide: choose the American people or bow down to President Trump and his coterie of billionaires," Schumer said in remarks on the floor. He later added, "Every senator will soon have an opportunity to reject this nonsense and vote for commonsense budgeting. Americans will be watching."

Senate Majority Leader John Thune, a Republican, defended the legislation as bringing tax cuts to American families and argued government programs like Medicaid are in need of reform.

"Mr. President, it's time to vote," Thune said. Thune added on Trump's bill, "This, Mr. President, will make this country safer, stronger and more prosperous."

House GOP leaders informed lawmakers Sunday night that their earliest vote on the "One Big Beautiful Bill" would occur Wednesday morning, as the Senate works through the measure and top Republicans aim to meet a self-imposed Independence Day deadline.

"Members are advised that votes are now expected in the House as early as 9 a.m. Wednesday, July 2. Please stay tuned to future updates for additional information regarding this week's schedule," a notice from Majority Whip Tom Emmer's office said.

Republican leaders have told members they will receive 48 hours' notice before a vote is called and will have 72 hours to review the bill text.

A lot needs to happen before the House -- which was supposed to be out of session this week for the holiday -- can even hold a floor vote on the megabill.

First, the Senate needs to pass the bill and send it back to the lower chamber. Then, the Rules Committee will convene to advance the bill to the floor -- which is expected to occur as early as Tuesday.

Speaker Mike Johnson and GOP leaders have been working through the weekend to lock down the votes even as several lawmakers expressed opposition to the Senate's version, which is still not finalized. Johnson can only afford to lose three defections if all members are voting and present.

California moderate Republican Rep. David Valadao said he will vote "no" given the Medicaid changes in the Senate bill.

"I support the reasonable provisions in H.R. 1 that protect Medicaid's long-term viability and ensure the program continues to serve our most vulnerable, but I will not support a final bill that eliminates vital funding streams our hospitals rely on, including provider taxes and state directed payments, or any provisions that punish expansion states," Valadao said in a statement Saturday.

Several conservatives like Reps. Chip Roy of Texas, Josh Breechen of Oklahoma and Eric Burlison of Missouri have also expressed opposition to the Senate's bill.

"I will not negotiate via X. But it's important to know that jamming us with a bill before we've had any chance to review the implications of major changes & re-writes, fluid scores, a high likelihood of violating the house framework (deficits), & tons of swamp buy-offs is bad," Roy said in a post on X Saturday.

House GOP leaders hosted a conference call Saturday instructing members to not publicize their concerns with the bill, according to multiple sources.

-ABC News' Lauren Peller

Senate Republicans announced Sunday that they planned a brief pause on the precession of events toward a final vote on the "One Big Beautiful Bill."

Senators will begin their vote-a-rama at 9 a.m. Monday, instead of the original early early morning start time that was anticipated. In the meantime, debate of the bill will continue on the Senate floor until senators finish or their time expires.

Once the vote-a-rama kicks off, senators will be allowed to offer an unlimited number amendments to the bill. When this ends, they'll take a vote of final passage. It will need 51 votes to pass.

-ABC News' Allison Pecorin