House Intelligence Committee Chairman Adam Schiff (D-CA) criticized White House staffers who didn’t appear before the committee Monday for their scheduled interviews saying it exposed President Donald Trump’s efforts to obstruct the ongoing impeachment investigation.

“This will be further evidence of an effort by the administration to obstruct the lawful and constitutional duties of congress,” Schiff said during his press conference.

Monday’s no-show list includes White House Chief of Staff Mick Mulvaney’s adviser Robert Blair and Office of Management and Budget official Brian McCormack. The committee was also set to hear from National Security Council lawyers Michael Ellis and John Eisenberg later Monday however, their lawyers indicated their clients will not comply with the committee’s subpoenas.

“This will only further add to the body of evidence on a potential obstruction of congress charge against the president,” Schiff said.

“Today we have four additional subpoenas to add to the list of a potential charge involving the president of the United States and his obstruction of our constitutional duties.”

Schiff released the transcripts of earlier closed-door testimonies delivered by former U.S. Ambassador to Ukraine Marie Yovanovitch and former Senior Advisor to the Secretary of State Ambassador P. Michael McKinley. Click here to read the full transcripts.

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