Military pressure may be needed to oust Syria’s President Bashar al-Assad, US Secretary of State John Kerry said in Saudi Arabia on Thursday.

“He’s lost any semblance of legitimacy, but we have no higher priority than disrupting and defeating Daesh… Ultimately a combination of diplomacy and pressure will be needed to bring about a political transition,” he told reporters, adding that “military pressure may be needed.”

Daesh is an Arabic acronym for the Islamic State group, which has seized swathes of Syria and Iraq.