WASHINGTON, D.C. — The House of Representatives on Sunday demanded that leaders of the U.S. Postal Service testify at an emergency oversight hearing Aug. 24 on mail delays as concerns grow that the Trump White House is trying to undermine the agency during the coronavirus pandemic while states expand mail-in voting options for the November presidential election.

The House Oversight and Reform Committee said it wants to hear from new Postmaster General Louis DeJoy and from the chair of the Postal Service board of governors, Robert Duncan.

In a letter to House Democrats, House Speaker Nancy Pelosi said that she is "calling upon the House to return to session later this week to vote on Oversight and Reform Committee Chairwoman [Carolyn] Maloney’s “Delivering for America Act,” which prohibits the Postal Service from implementing any changes to operations or level of service it had in place on January 1, 2020."

Pressure is increasing on DeJoy, a major Republican donor and ally of the president, who has said he is modernizing the money-losing agency to make it more efficient. DeJoy has made cuts in overtime for postal workers, imposed restrictions on transportation, and reduced the quantity and use of mail-processing equipment.

“The postmaster general and top Postal Service leadership must answer to the Congress and the American people as to why they are pushing these dangerous new policies that threaten to silence the voices of millions, just months before the election,” congressional Democrats said in a statement announcing the hearing.

The lawmakers included Pelosi and Maloney, as well as Sen. Minority Leader Chuck Schumer and Michigan Sen. Gary Peters, the top Democrat on the Senate Homeland Security and Governmental Affairs Committee.

Trump said that he was blocking a $25 billion emergency injection sought by the Postal Service, as well as a Democratic proposal to provide $3.6 billion in additional election money to the states. The Republican president worries that mail-in voting could cost him reelection. The money for the post office is intended yo help with processing an expected surge of mail-in ballots. Both funding requests have been tied up in congressional negotiations over a new coronavirus relief package.

On Saturday, Trump tried to massage his message, saying he supports increasing money for the Postal Service. He said he was refusing to capitulate to Democrats on other parts of the relief package, including funding for states weighed down by debt accumulated before the pandemic.

The Associated Press contributed to this report.