The call is at the center of an anonymous whistleblower complaint that alleged Trump used the powers of his office to pressure the foreign leader into investigating political rival and former Vice President Joe Biden.
The Wall Street Journal first reported Monday that Pompeo listened in on the call.
According to a summary of that call released by the White House last week, Trump asked Zelensky to look into Biden and his son, Hunter.
Pompeo's name was not mentioned in the whistleblower complaint, which was declassified and released last week.
As part of their formal impeachment inquiry, House Democrats issued a subpoena to Pompeo on Friday to obtain any documents related to the State Department's role in arranging conversations between Trump's personal lawyer Rudy Giuliani and Ukraine officials.
Giuliani posted a screenshot of a text message on Twitter last week that appeared to come from the now-resigned State Department special envoy to Ukraine, Kurt Volker. That message and allegations in the whistleblower complaint suggest that the State Department had a hand in Giuliani's role with Ukraine.
“I never talked to a Ukrainian official until the State Department called me and asked me to do it,” Giuliani told Fox News last week. “And then I reported to every conversation back to them.”
Giuliani was subpoenaed on Monday, and the House has also planned depositions with five State Department officials for the next two weeks as the impeachment probe progresses.
The whistleblower complaint lists another top State Department official, T. Ulrich Brechbuhl, as being on the call.
“Here’s what I’ll say this morning about the engagement of the State Department,” Pompeo told reporters last week, before he says he read the full complaint. “To the best of my knowledge, so from what I’ve seen so far, each of the actions that were undertaken by State Department officials was entirely appropriate and consistent with the objective that we’ve had certainly since this new government has come into office."
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Contributing: Deirdre Shesgreen
This article originally appeared on USA TODAY: Ukraine: Secretary of State Mike Pompeo was on the Trump phone call