Asked whether threatened U.S. military action to punish Syrian President Bashar Assad’s government would be legal, Ban insisted that “the Security Council has primary responsibility for international peace and security.”

“The use of force is lawful only when in exercise of self-defense in accordance with Article 51 of the United Nations Charter and-or when the Security Council approves such action,” Ban said.

“I take note of the argument for action to prevent a future use of chemical weapons,” the U.N. chief added. “At the same time, we must consider the impact of any punitive measure on efforts to prevent further bloodshed and facilitate the political resolution of the conflict.”

Ban appealed for Security Council member states to “come together on an appropriate response” to the chemical weapons issue. He also urged “regional and international actors to convene the Geneva conference as soon as possible.”