Three key committees in the process of putting together President Donald Trump’s “one big, beautiful bill” are expected to work through the night to advance their respective portions of the Republican agenda.

The House Agriculture Committee, the Energy & Commerce Committee and the Ways & Means Committee are all holding meetings aimed at advancing key parts of Trump’s bill.

Sources told Fox News Digital they expected the Energy & Commerce and Ways & Means meetings, which began on Tuesday afternoon, to last upwards of 20 hours each. The Agriculture panel’s markup is also expected to last into Wednesday.

Democrats on each committee, meanwhile, have prepared a barrage of attacks and accusations against GOP lawmakers looking to gut critical welfare programs.

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Sparks flew early at the Energy & Commerce Committee meeting with protesters both inside and outside the room repeatedly attempting to disrupt proceedings – with 26 people arrested by Capitol Police.

Protesters against Medicaid cuts, predominately in wheelchairs, remained outside the budget markup for several hours as representatives inside debated that and other critical facets under the committee’s broad jurisdiction.

Inside the budget markup, Democrats and Republicans sparred along party lines over Medicaid cuts. Democrats repeatedly claimed the Republican budget proposal will cut vital Medicaid services. 

Many Democrats shared how Medicaid services have saved their constituents’ lives and argued that millions of Americans could lose coverage under the current proposal.

Meanwhile, Republicans accused Democrats of lying to the American people about Medicaid cuts – a word Kentucky Republican Rep. Brett Guthrie, Chairman of the Energy and Commerce Committee, deterred his colleagues from using. Tensions arose when the word was repeated as Democrats called it a mischaracterization of their testimonies.

Republicans have contended that their bill only seeks to cut waste, fraud, and abuse of the Medicaid system, leaving more of its resources for vulnerable populations that truly need it. 

That committee was tasked with finding $880 billion in spending cuts to offset Trump’s other funding priorities. Guthrie told House Republicans on a call Sunday night that they’d found upwards of $900 billion in cuts.

Democrats have seized on Republican reforms to Medicaid, including heightened work requirements and shifting more costs to certain states, as a political cudgel. 

At one point late in the evening, House Minority Leader Hakeem Jeffries, D-N.Y., made an appearance at the Energy & Commerce panel’s meeting.

House Minority Leader Hakeem Jeffries showed up to the Energy & Commerce Committee hearing. (Tierney L. Cross/Bloomberg via Getty Images)

“I just want to mention our Democratic Leader Hakeem Jeffries is here because of his concern about Medicaid. Thank you,” the committee’s top Democrat, Rep. Frank Pallone, D-N.J., said.

But tensions remain between moderate Republicans and conservatives about the level of cuts the committee is seeking to the former Biden administration’s Inflation Reduction Act green energy tax subsidies.

The meeting at the Ways & Means Committee, the House’s tax-writing panel, had relatively little fanfare but was equally contentious as Democrats attempted to offer amendments to preserve Affordable Care Act tax credits and changes to the state and local tax (SALT) deduction cap.

At one point, Reps. Beth Van Duyne, R-Texas, and Tom Suozzi, D-N.Y., got into a heated exchange over SALT, with Suozzi pushing Van Duyne on whether she’d ever been to New York.

Van Duyne earlier called Texas a “donor state” in terms of taxes, arguing, “We should not have to pay to make up for the rich folks in New York who are getting raped by their local and state governments.”

Suozzi later pointed out Van Duyne was born and went to college in upstate New York – leading to audible gasps in the room.

Van Duyne said there was “a reason” she left.

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“We’re sorry you left New York, but in some ways it may have worked out better for all of us,” Suozzi said.

The SALT deduction cap, however, is still a politically tricky issue even as House lawmakers debate what Republicans hoped would be the final bill.

The legislation would raise the $10,000 SALT deduction cap to $30,000 for most single and married tax filers – a figure that Republicans in higher cost-of-living areas said was not enough.

Rep. Mike Lawler, R-N.Y., threatened to vote against the final bill if the new cap remains.

As the committee’s marathon meeting continued, a group of blue state Republicans are huddling with House GOP leaders to find a compromise on a way forward.

Rep. Nick LaLota, R-N.Y., hinted at tensions in the meeting when he posted on X that Rep. Nicole Malliotakis, R-N.Y., a member of the SALT Caucus and Ways & Means Committee, “wasn’t involved in today’s meeting” because her district required “something different than mine and the other most SALTY five.”

Malliotakis had told Fox News Digital she was supportive of the $30,000 cap. She’s also the only member of the SALT Caucus on the critical tax-writing panel.

Rep. Beth Van Duyne got into a heated back-and-forth with Rep. Tom Suozzi.

The Agriculture Committee, which began its meeting on Tuesday evening, saw Democrats waste no time in accusing Republicans of trying to gut the Supplemental Nutrition Assistance Program (SNAP), colloquially known as food stamps.

Rep. Adam Gray, D-Calif., accused Republicans of worrying that “somebody is getting a meal they didn’t deserve or kids are getting too fat” instead of more critical issues.

Republicans, like Rep. Randy Feenstra, R-Iowa, touted the bill’s inclusion of crop insurance for young farmers, increasing opportunity for export markets, and helping invest in national animal disaster centers aimed at preventing and mitigating livestock illness.

He also said Republicans were working to “secure” SNAP from waste and abuse.

House and Senate Republicans are working on Trump’s agenda via the budget reconciliation process, which allows the party in power to sideline the minority by lowering the Senate’s threshold for passage to a simple majority, provided the legislation at hand deals with spending, taxes or the national debt.

Trump wants Republicans to use the maneuver for a sweeping bill on his tax, border, immigration, energy and defense priorities.

Two sources familiar with the plan said the House Budget Committee intends to advance the full bill, the first step to getting the legislation to a House-wide vote, on Friday.