Attack on Saudi Arabia 'unprecedented': U.S. defense secretary

U.S. Defense Secretary Esper and Joint Chiefs Chairman Dunford hold news conference at the Pentagon in Arlington, Virginia

WASHINGTON (Reuters) - U.S. Defense Secretary Mark Esper said on Monday the recent attack on Saudi Arabian oil facilities was "unprecedented" and the United States, along with its allies, was working to defend the "international rules-based order that is being undermined by Iran."

Esper said on Twitter https://twitter.com/EsperDoD/status/1173660316351246336?s=20 he had returned to the Pentagon after a meeting at the White House, where Defense Department leadership and others briefed President Donald Trump on the situation.

Esper added that over the weekend he spoke with Saudi Arabia's crown prince and the Iraqi minister of defense.

(Reporting by Idrees Ali and Phil Stewart; Editing by Chris Reese)