Postmaster General Louis DeJoy is expected to testify before the Senate Homeland Security and Governmental Affairs Committee on Friday about the U.S. Postal Service amid the battle over mail-in ballots.

The panel, chaired by Sen. Ron Johnson, R-Wis., will hold a virtual hearing with DeJoy on Friday.

"I wanted to give the PMG an opportunity to tell his side of the story before he appeared before a hostile House committee," Johnson told Fox News Tuesday.

DEMOCRATS DEMAND POSTMASTER GENERAL, CHAIRMAN OF USPS TESTIFY ON MAIL-IN BALLOTS

The hearing comes after congressional Democrats over the weekend demanded DeJoy and the chairman of the U.S. Postal Service Board of Governors Robert Duncan testify over recent “sweeping and dangerous operational changes” at the agency that they claim are “slowing” the mail and “jeopardizing the integrity of the 2020 election.

The Democrats, over the weekend, called for DeJoy and Duncan to testify during an “urgent hearing” before the House Oversight Committee on Aug. 24. A source familiar with the plans told Fox News that DeJoy has agreed to appear Monday.

The demands came from House Speaker Nancy Pelosi, D-Calif., Senate Minority Leader Chuck Schumer, D-N.Y., House Oversight Committee Chair Carolyn Maloney, D-N.Y., and Sen. Gary Peters, D-Mich., the top Democrat on the Senate Homeland Security and Governmental Affairs Committee.

“I am pleased to have secured an oversight hearing on Friday with Postmaster General DeJoy in order to address urgent questions on the Postal Service delays that are causing massive disruptions across the country," Peters said in a statement Tuesday. "The Postal Service is a lifeline for Michiganders and Americans across the country who depend on reliable mail service, especially in rural communities – and we must ensure they can continue to count on dependable and timely delivery no matter where they live."

He added: "As ranking member on the only Senate Committee with oversight of the Postal Service, I will continue pressing for answers on Mr. DeJoy’s recent directives and their impacts on all Americans, who rely on the Postal Service for prescriptions, running their small businesses, voting and other crucial purposes.”

The Washington Post, on Tuesday, first reported that DeJoy would testify about the USPS’s vote-by-mail financial requirements.

Trump and the Republican Party have been warning for months about possible fraud connected to mail-in voting. The RNC and the Trump campaign have filed lawsuits to hit back against efforts by Democrats to overhaul voting laws in response to the pandemic; this, while Democrats say that cases of actual voter fraud are limited and claim that Republicans are trying to suppress voter turnout to improve their chances of winning elections.

“The president has explicitly stated his intention to manipulate the Postal Service to deny eligible voters access to the ballot in pursuit of his own reelection,” the Democrats wrote in a joint statement Sunday.

The Democrats went on to claim that DeJoy is a “Trump mega-donor” and has “acted as an accomplice in the president’s campaign to cheat in the election” by launching “sweeping new operational changes that degrade delivery standards and delay the mail.”

Last week, the USPS warned 46 states and the District of Columbia that it cannot guarantee all ballots cast by mail will arrive in time to be counted in the November election.

“This constitutes a grave threat to the integrity of the election and to our very democracy,” they wrote, referring to the USPS warning, which noted that even if voters meet every deadline and follow their state’s election procedures, their vote may not be counted.

Democrats have asked for $25 billion, including $3.5 billion in election resources, to fortify the Postal Service in time for the election to be included in the fourth coronavirus stimulus package. Trump has said the Postal Service money won’t be coming through unless Democrats come to the negotiating table on coronavirus relief and give concessions to Republicans.

FAUCI SAYS THERE IS 'NO REASON' AMERICANS CAN'T VOTE IN PERSON IN NOVEMBER

“Sure, if they give us what we want,” the president said of the post office money during a press conference Friday. “And it's not what I want, it's what the American people want.”

Trump on Thursday said mail-in voting would not be possible without the funding.

"It's their fault," Trump told FOX Business’ “Mornings with Maria.” "They want $3.5 billion for something that's fraudulent ... for the mail-in votes, universal mail-in ballots. They want $25 billion for the post office. They need that money so it can work and they can take these millions and millions of ballots.”

The president said vote-by-mail is contingent on the funding.

"But if they don't get those two items, then they can't have mail-in ballots," he said.

The president went on to slam voting by mail. He said ballots have been “sent to dogs” and "dead people," citing states like Virginia, where he said more than “500,000 phony ballot applications were sent to voters,” and in New York, where mail-in voting caused a weeks-long delay in announcing results for some races in the state's primary.

But former Vice President Joe Biden's campaign said casting ballots by mail is the “most secure form of voting" amid the novel coronavirus.

Meanwhile, National Institute of Allergy and Infectious Diseases Dr. Anthony Fauci said there is “no reason” Americans can’t vote in person for the 2020 presidential election, so long as voters follow proper social distancing guidelines amid the coronavirus pandemic.

“I think if carefully done, according to the guidelines, there’s no reason that I can see why that cannot be the case,” Fauci told ABC News this week. “If you go and wear a mask, if you observe the physical distancing, and don’t have a crowded situation, there’s no reason why [people] shouldn’t be able to do that.”

Fauci added that individuals who are “compromised physically or otherwise” and who are not interested in physically going to the polls on Election Day, can use mail-in voting.

But Fauci doubled down, saying “there’s no reason why we shouldn’t be able to vote in person or otherwise.”

Fox News' Chad Pergram and Kelly Phares contributed to this report.