WASHINGTON, Oct. 8 (Xinhua) -- The U.S. Department of State directed the country's ambassador to the European Union, Gordon Sondland, not to attend a congressional testimony on Tuesday related to the current administration's dealings with Ukraine, according to the diplomat's lawyer.
Robert Luskin, the attorney representing Sondland, said in a letter his client was ready to testify behind closed doors but the State Department instructed him not to show up, the reason for which was not given.
"He is a sitting ambassador and employee of State and is required to follow their direction," Luskin said. "Ambassador Sondland is profoundly disappointed that he will not be able to testify today."
Sondland is a key witness of the controversy surrounding a phone call on July 25 between U.S. President Donald Trump and Ukrainian President Volodymyr Zelensky which alarmed an intelligence official, who filed a whistleblower complaint on Aug. 12 alleging Trump's misconduct on the phone.
Secretary of State Mike Pompeo, in a meeting with Estonian foreign minister Urmas Reinsalu on Tuesday in Washington, ignored a question concerning the cancellation of Sondland's testimony.
House Speaker Nancy Pelosi announced on Sept. 24 the initiation of an impeachment inquiry into Trump. A rough transcript of the Trump-Zelensky conversation and a redacted version of the whistleblower complaint were released the following two days.
House Democrats probing the matter believed Trump pressured Zelensky to investigate, among others, Joe Biden, a Democratic presidential candidate for the 2020 U.S. election, allegations Trump has denied.
Documents containing text messages between U.S. and Ukrainian officials submitted to Congress on Thursday by former U.S. special envoy to Ukraine, Kurt Volker, showed that Sondland was involved in coordinating Washington's engagement with Zelensky's government before and after the presidential phone call. Zelensky, a former comedian, assumed office on May 20.
"Ambassador Sondland believes strongly that he acted at all times in the best interests of the United States, and he stands ready to answer the Committee's questions fully and truthfully," Luskin said in the letter.
As part of the impeachment inquiry, Sondland and Volker, along with three other State Department officials, were asked by a congressional subpoena issued on Sept. 27 to Pompeo to be deposed. Volker resigned from his post before a date was set for his deposition.