Former Ohio Gov. John Kasich (R) told CNN Friday that President Trump should be impeached after acting Chief of Staff Mick Mulvaney said the Trump administration had frozen military aid as leverage to get Ukraine to investigate a conspiracy theory about a DNC server.

"To me, it's totally inappropriate. It's an abuse of power. Now I know that there are presidents that will withhold aid because they have policy differences, but this is not a policy difference. So my view is that — look, I fought with people on the air about 'Is there a quid pro quo?' and 'Does this rise to the level of impeachment?' I now believe that it does. I say it with great sadness. This is not something I really wanted to do."

The big picture: Kasich has long been a political opponent of Trump — despite his prior hesitancy to call for the president's impeachment — and said he was "very seriously" considering a 2020 primary challenge as recently as last year.

Worth noting: Mulvaney walked back his quid pro quo comments after his on camera briefing on Thursday, claiming that "the media has decided to misconstrue my comments to advance a biased and political witch hunt against President Trump" in a later statement.

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