WASHINGTON, July 25 (Reuters) - Paul Manafort, who served as Donald Trump's campaign manager for several months last year, has started providing documents to the Senate Judiciary Committee in its investigation into possible Russian meddling in the 2016 U.S. election, the head of the panel said on Tuesday.

"Faced with issuance of a subpoena, we are happy that Mr. Manafort has started producing documents to the Committee and we have agreed to continue negotiating over a transcribed interview," Republican Senator Chuck Grassley, chairman of the panel, said in a statement. (Reporting by Patricia Zengerle; Writing by Washington Newsroom; Editing by Leslie Adler)