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On Friday, the White House dismissed yet another impeachment witness, Ambassador to the European Union Gordon Sondland, as President Donald Trump continued his apparent retaliation campaign to oust members of his administration who testified against him.

SONDLAND out as well: “I was advised today that the President intends to recall me effective immediately as United States Ambassador to the European Union,” he says in statement — Kevin Liptak (@Kevinliptakcnn) February 7, 2020

Sondland’s ouster comes just hours after the White House dismissed National Security Council aide Lt. Col. Alexander Vindman and his twin brother, Yevgeny, and reassigned them to Pentagon roles.

Sondland’s congressional testimony reinforced a core part of the House investigators’ case for impeaching Trump. The investigation centered on whether the president abused his power and obstructed justice when he withheld military aid from Ukraine in exchange for investigations into political opponents.

“As I testified previously, Mr. Giuliani’s requests were a quid pro quo for arranging a White House visit for President Zelensky,” Sondland said in testimony in November, referring to Trump’s attorney Rudy Giuliani, who helped with the pressure campaign. “Mr. Giuliani was expressing the desires of the President of the United States, and we knew that these investigations were important to the President.”

The House later voted to impeach the president on charges of abuse of power and obstruction of Congress. But the Senate voted this week to acquit the president, with Sen. Mitt Romney as the lone Republican to break party ranks and vote to remove Trump from office. On Thursday, during a rambling speech, Trump railed against his so-called political enemies, condemned the impeachment process as “evil,” referred to Romney as a “failed presidential candidate,” and lambasted House Speaker Nancy Pelosi and former FBI director James Comey.