Former White House chief of staff Mark Meadows will no longer cooperate with the House select committee investigating the Jan. 6 Capitol insurrection, the committee said Tuesday.

Why it matters: Meadows, who failed to appear before the panel last month, is believed to have insight into former President Trump's role in efforts to stop the certification of President Biden's election win.

• Last week, the committee and Meadows' attorney, George Terwilliger, said the parties had reached an understanding on how to exchange information.

What they're saying: "Tomorrow’s deposition will go forward as planned," the committee said in a tweet.

• "If indeed Mr. Meadows refuses to appear, the Select Committee will be left no choice but to advance contempt proceedings and recommend that the body in which Meadows once served refer him for criminal prosecution," it continued.

Terwilliger did not immediately respond to Axios' requests for comment but told Fox News, he had "made efforts over many weeks to reach an accommodation with the committee."

• Terwilliger said Meadows believed he would not be answering questions he said were protected by executive privilege. However, he said the committee indicated it wanted to address such matters, per Fox News.

Details: "We agreed to provide thousands of pages of responsive documents and Mr. Meadows was willing to appear voluntarily, not under compulsion of the Select Committee's subpoena to him, for a deposition to answer questions about non-privileged matters. Now actions by the Select Committee have made such an appearance untenable," Terwilliger said in a letter to the committee obtained by CNN.

• "[T]he Select Committee has no intention of respecting boundaries concerning Executive Privilege," he added.
• "As a result of careful and deliberate consideration of these factors, we now must decline the opportunity to appear voluntarily for a deposition."

This is a developing story. Please check back for updates.