The United States and Israel clashed with Iran at an emergency meeting of the U.N. Security Council on Saturday where the U.N. chief and many countries urged a halt to their attacks and a return to negotiations to prevent the conflict from spreading further into the region and beyond.

Axar.az reports, citing AP, that Secretary-General Antonio Guterres told the council that everything must be done to prevent an escalation.

“The alternative,” he warned, “is a potential wider conflict with grave consequences for civilians and regional stability.”

Guterres said the U.S. and Israeli airstrikes violated international law, including the U.N. Charter. He also condemned Iran’s retaliatory attacks for violating the sovereignty and territorial integrity of Bahrain, Iraq, Jordan, Kuwait, Qatar, Saudi Arabia and the United Arab Emirates.

The U.S. ambassador to the United Nations, Mike Waltz, insisted the U.S. military action was lawful.