House Speaker Nancy Pelosi responded to President Donald Trump's comments about his top Ukraine expert Lt. Col. Alexander Vindman's testimony, writing on Twitter, "Everybody has read your words on the call."

Pelosi notes that in the summary of the July 25 call released by the White House, Ukrainian President Volodymyr Zelensky asks for military aid to fight back against a Russian invasion, to which Trump replies "I want you to do us a favor though" and asks for investigations into his political opponents.

Earlier Tuesday, the president had tweeted criticism of Vindman.

"Was he on the same call that I was? Can't be possible!" the president tweeted of Vindman's planned testimony, also calling him a "Never Trumper."

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Vindman plans to tell the House Oversight, Foreign Affairs, and Intelligence Committees he was "concerned" by the July 25 call between Trump and Zelensky.

"I did not think it was proper to demand that a foreign government investigate a U.S. citizen, and I was worried about the implications for the U.S. government’s support of Ukraine," Vindman wrote. A copy of his planned testimony for Tuesday was obtained Monday evening by USA TODAY.

"I realized that if Ukraine pursued an investigation into the Bidens and Burisma, it would likely be interpreted as a partisan play which would undoubtedly result in Ukraine losing the bipartisan support it has thus far maintained," Vindman wrote in his testimony. "This would all undermine U.S. national security. Following the call, I again reported my concerns to NSC’s lead counsel."

Contributing: Christal Hayes, Savannah Behrmann