WASHINGTON — Postmaster General Louis DeJoy will testify at a Senate Homeland Security and Governmental Affairs Committee hearing on Friday about the U.S. Postal Service’s vote-by-mail financial requirements, according to two people familiar with the decision.

It will be DeJoy’s first opportunity to publicly answer lawmakers’ questions about the nation’s embattled mail service, which is experiencing delays as a result of policies DeJoy implemented cutting overtime and eliminating extra trips to ensure on-time mail delivery. DeJoy and USPS board of governors Chairman Robert M. Duncan are also set to testify before the House Oversight Committee on Monday.

Clamors from Democrats in both chambers for hearings with DeJoy grew over recent days after Trump said he wanted to withhold funding from the Postal Service to attempt to hobble its ability to process election mail.

Democrats have alleged that DeJoy, a former Republican National Convention finance chairman, is taking steps that are causing dysfunction in the mail system and could wreak havoc in the presidential election.

Republicans brush off those allegations, saying DeJoy must take decisive action to cut costs at the long-beleaguered agency.

A USPS representative did not immediately respond to a request for comment.

The Postal Service is in the process of removing 671 high-speed mail-sorting machines nationwide this month, a process that will eliminate 21.4 million items per hour’s worth of processing capability from the agency’s inventory.

On Thursday and Friday, it began removing public collection boxes in parts of California, New York, Pennsylvania, Oregon and Montana. The agency said Friday that it would stop mailbox removals, which it said were routine, until after the election.

And White House Chief of Staff Mark Meadows said on CNN’s “State of the Union” on Sunday that it would also halt sorting-machine removals.

Meadows also said the White House is open to Congress passing a stand-alone measure to ensure the U.S. Postal Service is adequately funded to manage a surge in mail voting in November.

“The president of the United States is not going to interfere with anybody casting their votes in a legitimate way whether it’s the post office or anything else,” he said.

Sen. Ron Johnson, R-Wis., the Senate committee chair, will gavel the Friday hearing remotely, and is expected to press DeJoy on whether the Postal Service truly needs the $25 billion in emergency funding that the House has pushed. The Trump administration has backed away from its hard line stance against any postal aid, and signaled it could be willing to approve $10 billion. The agency has $15 billion in cash and another $10 billion it can access in a Treasury loan. Analysts of its finances say that is more than enough liquidity for the Postal Service to make it through the November election. The Postal Service’s own estimates say it has enough cash on hand to survive through at least March.

Senate Democrats – including the party’s presumptive vice-presidential nominee Sen. Kamala Harris of California and Sen. Gary Peters of Michigan, who launched his own investigation of mail delays last week – are poised to grill DeJoy on his connections to the Trump White House.

DeJoy has given more than $2 million to the Trump campaign or Republican causes since 2016, according to the Federal Election Commission, including a $210,600 contribution to the Trump Victory Fund on Feb. 19. He has given more than $650,000 to the Trump Victory Fund and more than $1 million to the Republican National Convention. Democrats in both the House and Senate have labeled his selection patronage from the Trump administration.