FILE PHOTO: U.S. Defense Secretary James Mattis answers a question from the news media as U.S. President Donald Trump spoke during a gathering for a briefing from his senior military leaders in the Cabinet Room at the White House in Washington, U.S., October 23, 2018. REUTERS/Leah Millis/File Photo

WASHINGTON (Reuters) - Saudi Arabia plays a fundamental role in maintaining security in the Middle East, which cannot be dismissed even as the United States seeks accountability for the murder of Jamal Khashoggi, U.S. Secretary of Defense James Mattis told U.S. senators in a closed briefing on Wednesday.

“I must note we are seldom free to work with unblemished partners ... Our security interests cannot be dismissed, even as we seek accountability for what President Trump described as the ‘unacceptable and horrible crime’ of Jamal Khashoggi’s murder,” Mattis said, according to remarks sent to reporters.