A veteran prosecutor who served in various capacities in the Bush, Obama and Trump administrations called Secretary of State Mike Pompeo a “coward” Friday for not sticking up for U.S. diplomats abroad.

The criticism from Chuck Rosenberg, who served as acting DEA administrator during the first eight months of Trump’s tenure, came during a break in the testimony of ousted U.S. Ambassador to Ukraine Marie Yovanovitch.

Rosenberg was reacting to Yovanovitch’s description of a July call between Trump and Ukrainian President Volodymyr Zelensky, in which Trump attacked Yovanovitch and said “she’s going to go through some things.” Yovanovitch said she felt threatened upon learning about Trump’s remarks, which were released by the White House in September.

Multiple impeachment inquiry witnesses have testified that they unsuccessfully lobbied Pompeo to release a statement supporting Yovanovitch after the White House released the memorandum of the call showing Trump’s attacks.

“His silence is deafening, it is an act of abject cowardice,” Rosenberg said of Pompeo. “I’m astonished that somebody who went to West Point and was an Army officer does not have the spine to stand up for the people in his organization who are being denigrated by this President.”

Rosenberg called Pompeo’s silence a “complete failure of leadership,” and “disgusting,” and said if Pompeo were watching, “I would tell him he’s a coward.”

Rosenberg previously served as U.S. attorney for the Eastern District of Virginia and acting U.S. attorney for the Southern District of Texas during George W. Bush’s second term.

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