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President Donald Trump's Acting Chief of Staff Mick Mulvaney openly admitted during a press briefing Thursday that the White House withheld military aid to Ukraine to pressure that country to investigate so-called "corruption" by Democrats in the 2016 election.

"The look-back to what happened in 2016 certainly was part of the thing that [Trump] was worried about in corruption with that nation. And that is absolutely appropriate," said Mulvaney. "Did he also mention to me in passing the corruption related to the DNC. server? Absolutely. No question about that. But that's it, and that's why we held up the money."

The New York Times noted that Mulvaney was "referring to Mr. Trump's discredited idea that a server with Hillary Clinton's missing emails was being held by a company based in Ukraine."

Jon Karl, chief White House correspondent for ABC News, pointed out to Mulvaney that what he described "is a quid pro quo."

"It is funding will not flow unless the investigation into the Democratic server happened," said Karl.

Mulvaney didn't reject Karl's characterization.

"We do that all the time with foreign policy," said Mulvaney. "Get over it. There's going to be political influence in foreign policy... That is going to happen. Elections have consequences."

Watch:

"To be clear, what you described is a quid pro quo" -- Here's Mick Mulvaney casually admitting that Trump held up aid to Ukraine as leverage to get the Ukrainian government to investigate the 2016 election pic.twitter.com/ylz7BKEmKd — Aaron Rupar (@atrupar) October 17, 2019

"To all the Republicans that denied the quid pro quo—feel free to release your statements backtracking now," said Rep. Mark Pocan (D-Wis.), co-chair of the Congressional Progressive Caucus in response to Mulvaney's remarks.

GOP talking points three weeks ago: the call transcript shows NO quid pro quo! Mulvaney today: of course there was a quid pro quo. That’s how you do foreign policy. — Sam Stein (@samstein) October 17, 2019 Mulvaney admits the quid pro quo out loud. Amazing. https://t.co/x2g6Ru4UZ7 — Renato Mariotti (@renato_mariotti) October 17, 2019

Matt Duss, foreign policy adviser to Sen. Bernie Sanders (I-Vt.), tweeted, "For those just joining us, Mulvaney just straight up admitted that this administration sees no difference between using U.S. aid to advance national policy goals and using it to advance Trump's personal political goals."