By KATHERINE FAULDERS and LIBBY CATHEY, ABC News

(WASHINGTON) — Postmaster General Louis DeJoy on Tuesday agreed to testify on Friday before Senate lawmakers, setting up President Donald Trump’s controversial pick for two blockbuster hearings within a few days amid a political firestorm over mail-in voting and claims that President Donald Trump is trying to “sabotage” the November election.

After Senate Homeland Security and Governmental Affairs Committee Chairman Ron Johnson, R-Wis., announced the Friday hearing, Senate Majority Leader Chuck Schumer credited “immense pressure from Senate Democrats and the American people” with having “forced Senate Republicans to confront Postmaster General DeJoy’s ongoing sabotage of the Postal Service.”

While some Republicans have expressed concerns about service cutbacks at the Postal Service, they could also use the hearing to try to push back on Democratic claims and to reinforce claims made by Trump.

The announcement of a Senate hearing comes after House Democrats said Monday that DeJoy agreed to their demand that he testify next week about controversial changes he’s making to the Postal Service.

It didn’t take long for Trump to criticize the move.

House Oversight and Reform Chairman Rep. Carolyn Maloney, D-N.Y., said in a statement Monday she was “pleased” that DeJoy has agreed to testify about “the sweeping operational and organizational changes he has been making to the Postal Service.”

“I also look forward to receiving his production of documents and other information by this Friday in response to the detailed request I made last week with Speaker Pelosi, Leader Schumer, Chairperson Lofgren, and Senate Ranking Members Peters and Klobuchar,” the statement continued. “The American people want their mail, medicines, and mail-in ballots delivered in a timely way, and they certainly do not want drastic changes and delays in the midst of a global pandemic just months before the election.”

DeJoy was previously scheduled to testify on Sept. 17, which he had indicated was his first availability according to the committee, but several Democrats requested that Maloney move up the hearing amid mounting mail-in voting concerns.

He’s currently slated to appear before the Senate Homeland Security and Governmental Affairs Committee in a virtual hearing on Friday at 9 a.m. and before the House Oversight and Reform Committee on Monday, Aug. 24, at 10 a.m.

In letters sent Sunday, Maloney called on DeJoy and Robert Duncan, the chairman of the Postal Service’s Board of Governors, to produce documents requested by the committee by Friday and to testify next Monday. Both officials were asked to respond with one week’s notice about whether they intended to comply voluntarily with the amended timeline.

Maloney confirmed in a House Democrats caucus call on Monday that the Postal Service inspector general is investigating DeJoy’s conflicts of interest and all staffing and policy changes he has implemented.

Majority Leader Steny Hoyer, D-Md., said the House vote on a bill aimed at reversing organizational and structural changes to the Postal Service made under DeJoy will likely take place on Saturday as early as 11 a.m.

Trump on Monday afternoon criticized the new hearing date, noting in a tweet that it conflicts with the first day of the Republican National Convention. He called on Republicans to “GET TOUGH.”

Why is Congress scheduled to meet (on Post Office) next Monday, during the Republican Convention, rather than now, while the Dems are having their Convention. They are always playing games. GET TOUGH REPUBLICANS!!!

— Donald J. Trump (@realDonaldTrump) August 17, 2020

The president has described DeJoy, who was appointed by him in June, as someone who wants to “make the post office great again.” Asked earlier Monday if he’s ever asked DeJoy to slow the mail, Trump said, “no” and he “wouldn’t do that.”

“I have encouraged everybody to speed up the mail, not slow the mail. And I also want to have a post office that runs without losing billions and billions of dollars a year as it has been doing for 50 years,” he said.

But a group of Democratic state attorneys general are now in the final stages of preparing legal action against the Trump administration for recent cost-cutting changes made to the Postal Service — and a growing number of lawmakers want Trump’s postmaster pick investigated, they say, for potentially breaking the law.

Rep. Hakeem Jeffries, D-N.Y. and Rep. Ted Lieu, D-Calif., on Monday called for FBI Director Christopher Wray to open a criminal probe into DeJoy, accusing him of deliberately slowing the mail to give Trump an advantage in the November election.

“There is overwhelming evidence that Postmaster General DeJoy and the Board of Governors have hindered the passage of mail,” the two Democrats on the House Judiciary Committee wrote in a letter to Wray.

Members of Maryland’s congressional delegation in a press conference Monday afternoon outside a Baltimore mail processing facility also accused Trump and DeJoy of “sabotaging” the Postal Service.

Sen. Chris Van Hollen, D-Md., calling on the Senate to reconvene and investigate the matter, said he and other lawmakers represented there had heard from constituents relying on the post office due to the pandemic about delayed deliveries in recent weeks from medications to social security checks.

“President Trump has reportedly already cast his vote by mail. … But apparently he wants to make it harder for other people’s ballots to be delivered on time,” said Van Hollen. “Make no mistake, this is part of a deliberate effort by the president of the United States to put out lies and misinformation.”

Sen. Ben Cardin, D-Md, called DeJoy’s action to raise the cost of voting by mail “a poll tax … trying to make it more difficult.”

“That’s unconscionable in a democracy,” he added.

And last Friday Rep. Bill Pascrell Jr., D-N.J., made a criminal referral to New Jersey Attorney General Gurbir Grewal, asking him to impanel a grand jury to investigate “subversion of election laws by Donald Trump, Louis DeJoy, and other Trump officials in their accelerating arson of the Post Office.”

In a press release Monday afternoon, Schumer re-upped his call to Johnson to call a Senate hearing with DeJoy, after saying in a press conference Sunday that DeJoy should be removed from his post if he refuses to appear.

“If Mr. DeJoy refuses to appear he should be stamped return to sender,” Schumer said Sunday. “He should not be allowed to be the postmaster general if after all this destruction he can’t answer to the American people what he is doing.”

Even GOP Sen. Susan Collins of Maine has broken with the president on the issue and urged the United States Postal Service to reverse cuts, calling the post office a “lifeline” for rural communities.

“I write to request that you promptly address the delays in mail delivery that have occurred following recent operational changes at the United States Postal Service,” Collins wrote in a letter to DeJoy last week. “While I support efforts to improve the USPS’s financial condition, I am concerned that the reported changes will have the opposite effect, reducing service to the public and driving away customers.”

Schumer was among several top Democrats including House Speaker Nancy Pelosi who signed a 10-page letter to DeJoy sent last week calling for documents to be produced by Friday.

“We urge you not to increase costs for election officials and to direct all Postal Service employees to continue to prioritize delivery of election mail so that voters and election workers have ample time to request and send election mail,” the letter said.

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