Hope Hicks just agreed to testify about the Mueller probe, which is a huge win for Congress

J. Scott Applewhite/AP

Former WH communications director Hope Hicks.

• Former White House communications director Hope Hicks has agreed to testify before the House Judiciary Committee next week.
• Hicks is the first material witness connected to the former special counsel Robert Mueller's Russia probe to appear before the panel.
• Her decision is especially noteworthy given that the White House instructed her - and all other witnesses who have been called to testify regarding the Mueller report - not to comply with the committee's subpoena for documents and testimony.
• Hicks may refuse to answer some questions relating to her time in the White House because of executive-privilege issues.
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The former White House communications director, Hope Hicks, has agreed to testify before the House Judiciary Committee in a closed-door session next week, the panel's chairman, Rep. Jerry Nadler, announced in a statement.

The interview will include questions related to the former special counsel Robert Mueller's Russia investigation, as well as "efforts by President Trump, his associates, and other Administration officials to obstruct justice and investigations into Presidential misconduct," the statement said.

Hicks is the first material witness connected to the Mueller probe to agree to testify before Congress. Her decision is especially significant given that the White House instructed her - as well as all other witnesses who have so far been called to testify - earlier this month not to comply with the committee's subpoena for documents and testimony.

Nadler's statement left open the possibility, however, that Hicks may refuse to answer certain questions due to issues of executive privilege. Should that case arise, Nadler said, "we will attempt to resolve any disagreement while reserving our right to take any and all measures in response to unfounded privilege assertions."

A transcript of Hicks' testimony will be made available to the public as well.

Hicks has long been a central figure in Trump's orbit and is one of his closest confidants. She left the White House last year, but prior to that, she was also witness to several episodes Mueller examined as part of his obstruction case.