The U.S. special envoy for Ukraine, Kurt Volker, resigned Friday amid a formal impeachment inquiry of President Donald Trump and his dealings with the Ukraine government, according to two people with knowledge of the matter.
Rudy Giuliani, Trump's personal lawyer, said Thursday that Volker had encouraged him to speak to Ukranian officials regarding former Vice President Joe Biden and his family.
In the complaint that sparked the impeachment inquiry, a whistleblower said that the day after Trump's July call with Ukraine President Volodymyr Zelenskiy, Volker traveled to the Ukrainian capital to meet with the leader.
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Volker has not responded to requests for comment from NBC News on Friday. The State Department is also not yet commenting.
One of the people with knowledge of the matter said that Volker stepping down from the position will enable him to be much freer in what he can say if he is called to testify before Congress.
On Friday, three House committees conducting the impeachment inquiry sent a letter to Secretary of State Mike Pompeo notifying him that multiple officials under his charge, including Volker, are subject to depositions before Congress.
Volker's deposition was scheduled for Oct. 3, although it was not clear if he would participate.
The letter, signed by U.S. Reps. Eliot L. Engel, D-New York, Rep. Adam Schiff, D-California, and Rep. Elijah E. Cummings, D-Maryland, states that Volker "played a direct role in arranging meetings between Rudy Giuliani, who has no official role in the U.S. government, and representatives of President Zelensky."