Updated 7:09 p.m. ET

President Trump on Thursday attempted to soften remarks he had made hours earlier in which he appeared to confirm that he opposes Democrats' proposed boost in funding for the U.S. Postal Service because he wants to make it harder to expand voting by mail, claiming his only goal in denying the agency funds is to ensure the integrity of the Nov. 3 election.

While Trump has long railed against mail-in voting, falsely claiming it leads to rampant fraud, during his regular briefing to reporters Thursday, he said he would not veto a coronavirus relief bill just because it included support for the Postal Service. However, he continued to push the unsubstantiated claim that widespread voting by mail would lead to an abuse of the system.

"We want people to vote, but we want people to vote so when they vote it means one vote," Trump said.

"I'm not doing this for any reason," Trump said, referring to his push to deny the agency funds. "Maybe the other turns out to be my advantage. I don't know, I can't tell you that. But I do know this: I just want an accurate vote."

Trump was responding to questions about comments in a Thursday morning interview with Fox Business Network's Maria Bartiromo, who had asked why the White House and congressional Democrats are still miles apart on approving a new relief deal.

Trump said one major factor is the Democrats' push for an injection of funds into the Postal Service to expand voting by mail.

"They [the Democrats] want $3 1/2 billion for something that'll turn out to be fraudulent — that's election money basically," Trump said.

Continued the president: "They want $25 billion for the post office. Now, they need that money in order to have the post office work so it can take all of these millions and millions of ballots. Now, in the meantime, they aren't getting there. But if they don't get those two items, that means you can't have universal mail-in voting because they're not equipped to have it."

Eight states are mailing ballots to all active voters this fall, including five that have been doing so for years, but most states are not conducting what Trump calls universal mail-in voting.

Trump continued: "If we don't make a deal, that means they don't get the money. That means they can't have universal mail-in voting. They just can't have it."

During his Thursday briefing to reporters, Trump reiterated that stance, saying: "We have to have an honest election, and if it's not going to be an honest election, I guess people have to sit down and think really long and hard about it."

"If they're not going to approve a bill, and the post office, therefore, won't have the money, and if they're not going to approve a big bill — a bigger bill — and they're not going to have the $3 1/2 billion for the universal mail-in votes, how can you have those votes?"

"What [it] would mean is the people will have to go to the polls and vote like the old days, like two years ago, three years ago. ... It doesn't say anybody is taking the vote away, but it means that the universal mail-ins don't work," Trump said.

Pressed on what that means for Americans who would be reluctant to vote in public for fear of the coronavirus, Trump said: "They're going to have to feel safe, and they will be safe. And we will make sure that they're safe, and we're not going to have to spend $3 1/2 billion to do it."

House Speaker Nancy Pelosi said in her weekly press conference Thursday that if funding for the Postal Service is a red line in negotiations, it's news to her.

"What [negotiators] are saying is different than what the president is saying," she said. "If they came in the room and said the president is never doing this, that's something we'd take to the American people. And the American people want the Postal Service protected and preserved."

Pelosi's statement on the negotiations also differs from what White House economic adviser Larry Kudlow has said.

"So [many] of the Democratic asks are really liberal, left wish lists — voting rights and aid to aliens and so forth," Kudlow told CNBC on Thursday. "That's not our game, and the president can't accept that kind of deal."

Pelosi told reporters the $25 billion allocated for the Postal Service in the HEROES Act is a figure recommended by the board of governors of the Postal Service. She stressed that Americans rely on the Postal Service to deliver, among other things, prescription drugs and paychecks to workers.

Biden campaign says Trump "sabotaging a basic service"

The campaign of the Democratic presumptive presidential nominee, former Vice President Joe Biden, quickly responded to Trump's interview, calling his intentions an "assault on democracy."

"The president of the United States is sabotaging a basic service that hundreds of millions of people rely upon, cutting a critical lifeline for rural economies and for delivery of medicines, because he wants to deprive Americans of their fundamental right to vote safely during the most catastrophic public health crisis in over 100 years — a crisis so devastatingly worsened by his own failed leadership that we are now the hardest hit country in the world by the coronavirus pandemic," Biden campaign spokesperson Andrew Bates said in a statement.

It isn't the first time this week that the president has lambasted voting by mail.

On Wednesday, he devoted a considerable amount of time during his daily briefing with reporters to denounce any plans for additional funding to support the Postal Service.

"Now they want to take it countrywide — mail-in voting. It's going to be the greatest fraud in the history of elections. When you always talk about Russia, Russia, Russia and China, Iran on voting — the biggest problem is going to be with the Democrats, not with China, Russia and Iran," he said.

Experts have estimated that as many as 70% of votes could be cast by mail in this election cycle because of disruptions caused by the pandemic. That estimate has raised questions about the long-beleaguered Postal Service, which was losing money well before the COVID-19 disaster and has been put into an even more difficult position.

Trump asserted in his Fox Business interview that there's "nothing wrong with getting out and voting," citing people who did so during World War I and II, but health experts said that voting by mail could reduce people's exposure and spread of the coronavirus.

Election watchdogs denounced Trump's latest comments.

"Trump's brazen abuse of the post office to try and win an election is a shameful misuse of presidential power," said Trevor Potter, president of the Campaign Legal Center and former Republican chair of the Federal Election Commission. "Defunding the Postal Service and slowing its ability to deliver mail ballots to Americans will hurt Democratic and Republican voters alike."

The Declaration for American Democracy, a coalition of more than 160 organizations, weighed in, too.

"President Trump made clear today that he is intentionally sabotaging the U.S. Post Office and blocking election funding to suppress Americans' votes. This act is a disgrace and a stain on our democracy," it said.

NPR's Claudia Grisales contributed to this report.

Correction: August 14, 2020 12:00 am — A previous version of this story incorrectly stated that six states have been mailing ballots to all active voters for years. It is actually five states.

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