Democratic Rep. Adam Schiff of California, chairman of the House Intelligence Committee, said Sunday he has given Michael Cohen a date to testify before his panel, "either voluntarily, or if necessary, by subpoena." Cohen, President Trump's former personal attorney, has already agreed to testify publicly before the House Oversight Committee on Feb. 7, weeks before he begins serving a three-year prison sentence.

Schiff's call for Cohen to testify comes in the wake of last week's BuzzFeed News report that special counsel Robert Mueller has evidence that Mr. Trump directed Cohen to lie to Congress. A spokesman for Mueller issued a rare statement disputing the report, saying, "BuzzFeed's description of specific statements to the special counsel's office, and characterization of documents and testimony obtained by this office, regarding Michael Cohen's Congressional testimony are not accurate."

Asked about the story, Schiff on Sunday emphasized the "need to pay particular attention to what we do know from the special counsel that was not included in this statement yesterday."

"What we do know from the special counsel is that Michael Cohen has shared information about core matters of the Russian investigation that he learned from people associated with the Trump Organization, the business organization. We also know from the special counsel that he has shared information about his communications with people associated with the White House during 2017 and 2018," he said.

Cohen pleaded guilty in November 2018 to one charge of lying to Congress for misleading the House and Senate Intelligence Committees about a potential real estate deal to build a Trump Tower in Moscow. Cohen said in correspondence with congressional investigators that discussions about the project ended much earlier than they in fact had.

Cohen previously pleaded guilty to campaign finance and fraud charges in August 2018, and was sentenced to three years in federal prison in December. He is set to begin his sentence in March.

On Sunday, Schiff said that the statement from the special counsel's office about the BuzzFeed story may have to do with "wanting to be able to use Michael Cohen as a witness in further prosecutions, and wanting to make sure that the public didn't have a perception that he was saying more than he was saying at least to the special counsel."

"There is a lot more to learn," Schiff said. "Congress has a fundamental interest in two things: First, in getting to the bottom of why a witness came before us and lied, and who else was knowledgeable that this was a lie."

Schiff said his committee would do everything it could to make any eventual report by the special counsel public. William Barr, Mr. Trump's nominee to be the next attorney general, declined to commit to releasing the report in its entirety during confirmation hearings last week.

"Because they will fight us on this, we need to do our own investigations, because at the end of the day if the Justice Department tries to stonewall the release of that report for whatever reason, the American people are going to need to know what happened, and we're going to have to press forth," Schiff said.