Acting White House Chief of Staff Mick Mulvaney told Fox News Sunday morning that the House Democrats will “never” see President Trump’s tax returns, setting the White House stance on an issue that has roiled Washington over the past week.

Pushing back in what could be a losing battle, Mulvaney added, “Nor should they. That’s an issue that was already litigated during the election. Voters knew the president could have given his tax returns. They knew that he didn’t and they elected him anyway.”

Last week, House Ways and Means Chairman Richard Neal, a Democrat, wrote a letter to IRS Commissioner Chuck Rettig and demanded the agency deliver six years worth of the president’s personal and business returns.

Neal gave the IRS a deadline of April 10, citing a federal tax quote that states the Treasury has an obligation to turn over the records upon such a request.

The president maintains that he cannot deliver the tax returns because of an ongoing audit. “We’re under audit, despite what people said, and we’re working that out,” Trump told reporters last week. “I’m always under audit, it seems. But I’ve been under audit for many years because the numbers are big, and I guess when you have a name, you’re audited.”

Mulvaney said that Democrats “know they're not going to get the tax returns.”

“They just want attention on the issue because they don’t want to talk to us about policy,” he said.

“They know one of the fundamental principles of the IRS is to protect the confidentiality of you and me and everybody else who files taxes,” Mulvaney added. “They know that. They know the terms under law by which the IRS can give them the documents, but ‘political hit job’ is not one of those reasons.”

Democratic Representative Dan Kildee, who is on the committee seeking Trump’s returns, told ABC News that the president and his lawyers are wrong about the law.

“This is a legitimate authority that the Congress has,” Kildee said. “This president, by the way, is the least transparent president that we’ve had in half a century.”

Kildee said that the president would not have the final word on whether his tax returns are released. “It is not up to President Trump, it is not up to some lawyer that President Trump hires, to determine whether his tax returns can be sought,” Kildee said. “This is not an autocracy. The president does not get to decide for himself and for Congress what a legitimate subject of inquiry might be.”