The House Intelligence Committee’s top Democrat said Friday that it would be “a serious mistake” not to hold public committee hearings related to the investigation into Russia’s interference in the 2016 election.

Rep. Adam Schiff, a Democrat, told reporters that the committee’s chairman, Rep. Devin Nunes, a Republican, had canceled an open intelligence committee hearing. The hearing, with former Director of National Intelligence James Clapper, former CIA Director John Brennan and former acting Attorney General Sally Yates, was set to take place next week.

“We don’t welcome cutting off the public access to information when we have witnesses who are willing to testify in an open session,” Schiff said Friday.

Schiff spoke to reporters minutes after Nunes held an unexpected press conference of his own announcing that Trump’s former campaign chairman, Paul Manafort, had agreed to be interviewed by the committee.

With regard to Manafort’s testimony, Schiff said he would “welcome it” if Manafort agreed to be interviewed in an open session, while Nunes said that he will allow Manafort to decide whether that hearing will be open or closed.

Nunes, in his earlier statements, did not mention cancelling the open hearing with Clapper, Brennan, and Yates. But he said he invited FBI Director James Comey and National Security Agency Director Mike Rogers back to the committee next week to testify before members in a closed session.

Comey and Rogers testified before the committee in a public hearing on Monday and disclosed the existence of an investigation into possible collusion between the Trump campaign and Russia during the election.

Schiff said that he was “not encouraged” by the events that unfolded in the days after the public hearing, beginning on Wednesday when Nunes announced that he had obtained documents from “a source” relating to surveillance of Trump’s transition team.

Nunes then went to the White House to brief the president on the information without showing the documents to Schiff, or anyone else on the committee, beforehand. Nunes later claimed that he could not brief Schiff or his fellow committee members because he did not have the documents in his possession, and was expecting to receive them from the NSA sometime next week.

Schiff, however, appeared unnerved by Nunes’ actions.

“To take evidence that may or may not be related to an investigation into Trump and his associates to the White House was wholly inappropriate,” Schiff said. “All of us are essentially in the dark.”

When asked if he thought that Nunes should recuse himself from the investigation into Trump’s Russia ties, Schiff replied that “that’s a decision that [House Speaker] Paul Ryan needs to make.”

He added that Trump “is now interfering in this investigation.”

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