“If the Middle East is unstable, the world will not be at peace,” Chinese President Xi Jinping said Thursday. “If the conflict escalates further, not only will the conflicting parties suffer greater losses, but regional countries will also suffer greatly.”

The S&P 500 and Nasdaq ended lower on Friday, with investors on edge over the Iran-Israel conflict heading into the weekend, as the U.S. considers whether to get involved. Trading was choppy for much of the session.