An attorney for Ambassador Gordon Sondland says the State Department has directed Sondland not to appear for his scheduled interview before a joint House committee taking depositions in the impeachment probe of President Donald Trump.

Sondland is wrapped up in the congressional impeachment inquiry and had previously agreed to appear voluntarily Tuesday to answer the committee's questions in a closed session.

Sondland attorney Robert Luskin says that as the sitting U.S. ambassador to the European Union and an employee of the State Department, Sondland is required to follow the department's direction. No reason for the direction was cited, he said.

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Luskin says Sondland "is profoundly disappointed that he will not be able to testify."

Luskin says Sondland "believes strongly that he acted at all times in the best interests of the United States."