FILE PHOTO: U.S. Attorney General William Barr listens to a question as he testifies during a Senate Judiciary Committee hearing on "the Justice Department's investigation of Russian interference with the 2016 presidential election" on Capitol Hill in Washington, U.S., May 1, 2019. REUTERS/Clodagh Kilcoyne/File Photo

WASHINGTON (Reuters) - A second congressional subpoena deadline for U.S. Attorney General William Barr to provide lawmakers with an unredacted copy of Special Counsel Robert Mueller’s Russia investigation report expired at 9 a.m. EDT (1300 GMT) on Monday.

It was not immediately clear whether Barr complied with the subpoena. Lawmakers have threatened to begin contempt of Congress proceedings against him, if he missed it.

House Judiciary Committee Chairman Jerrold Nadler subpoenaed the full Mueller report and underlying evidence on April 19. Barr missed an initial subpoena deadline for the material last week.