US Secretary of State John Kerry said Thursday that some countries might be prepared to send peacekeeping troops to Syria, as the UN leads efforts to bring the warring sides together and end the war.

The top US diplomat also acknowledged in an interview with Dubai-based Al-Arabiya television that President Bashar al-Assad was not ready to make peace.

Kerry was speaking a day after telling the opening of a peace conference in Switzerland that the Syrian leader could have no role in any future transitional government after three years of war.