Felix Sater, the chief negotiator on the Trump Tower Moscow project, failed to fully cooperate with the House Intelligence Committee, the Democratic majority said on Tuesday.

A spokesman for Chairman Adam Schiff disputed Sater saying after his closed-door interview on Tuesday that he had fully cooperated with the panel and his attorney saying his client did not invoke privilege.

"While we do not typically comment on closed interviews, given Mr. Sater's public comments that he has fully cooperated with the Committee and answered every question asked of him, we must correct the record. Mr. Sater has not fully cooperated with the Committee, and he will remain under subpoena until he does so," Schiff spokesman Patrick Boland said in a statement.

"Mr. Sater must produce all of the documents that were subpoenaed when he failed to show up for his last appearance, including unredacted telephone records, documents related to a joint defense agreement, and other documents we believe to the in his possession. In addition, contrary to his post-interview comments, Mr. Sater asserted a baseless claim of attorney-client privilege in response to question about Michael Cohen's false statement submitted to the Committee in August 2017. Our investigation thus far has revealed that Sater was not a part of any joint defense agreement, and has no basis to assert his privilege over these documents," Boland added. "The Committee will continue to pursue documents and testimony related to obstruction of the Committee's investigation."

Sater is a key witness in House Democrats' investigation into President Trump’s ties with Russia. He was scheduled to testify voluntarily last month but never showed, after which the committee issued a subpoena. Sater blamed this nonappearance on health issues.

Sater worked with former Trump attorney Michael Cohen to build a Trump Tower in Moscow in 2015 and 2016. The proposed skyscraper was never built. Cohen is currently serving time in prison for tax fraud and other crimes.