WASHINGTON — Mick Mulvaney, the acting White House chief of staff, threw the Trump administration’s defense against impeachment into disarray on Thursday when he said that the White House withheld nearly $400 million in military aid to Ukraine to further President Trump’s political interests.
Mr. Mulvaney told journalists in a televised White House briefing that the aid was withheld in part until Ukraine investigated an unsubstantiated theory that Ukraine, not Russia, was responsible for hacking Democratic Party emails in 2016 — a theory that would show that Mr. Trump was elected without Russian help.
The declaration by Mr. Mulvaney, which he took back later in the day, undercut Mr. Trump’s repeated denials of a quid pro quo that linked American military aid for Ukraine to an investigation that could help Mr. Trump politically.