(CNN) The chairman of the House Judiciary Committee is demanding that Attorney General William Barr explain how the Justice Department is receiving information on Ukraine from President Donald Trump's personal attorney, Rudy Giuliani.

Judiciary Chairman Jerry Nadler of New York sent a letter to Barr on Monday demanding details on the arrangement Giuliani has with the Justice Department to provide political dirt he's been digging up in Ukraine.

"As you know, the Department has formal, established channels by which to receive information and begin investigations," wrote Nadler. "This new channel to Mr. Giuliani would seem to be a significant departure from those traditional channels."

Barr on Monday confirmed that the Justice Department has been receiving information from Giuliani on Ukraine, saying DOJ has an "obligation to have an open door to anybody who wishes to provide us information that they think is relevant." He added there's skepticism about anything from Ukraine, which has prompted the department to establish an "intake process in the field" so the Justice Department and intelligence community can scrutinize Ukraine information.

"That is true for all information that comes to the Department relating to the Ukraine including anything that Mr. Giuliani might provide," Barr said.

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