Military pressure may be needed to topple Syrian President Bashar Al-Assad, US Secretary of State John Kerry said yesterday.
"He's lost any semblance of legitimacy, but we have no higher priority than disrupting and defeating ISIS and other terror networks," he told reporters.
"Ultimately a combination of diplomacy and pressure will be needed to bring about a political transition," he said, adding: "Military pressure particularly may be necessary given President Assad's reluctance to negotiate seriously."
Kerry arrived in Riyadh where he met with GCC foreign ministers yesterday to brief them on the progress of nuclear talks with Iran and discuss multiple conflicts raging in the Middle East.
Kerry said that Washington continues to observe Iran's actions which "destabilise the region".
"Even if we go into these talks with Iran on this programme, we will not overlook Iran's acts which cause instability in the region mainly in Syria and Yemen," he said.