The "nationwide cessation of hostilities" set to be implemented in Syria by world powers in one week's time will not apply to the Islamic State militant group, US Secretary of State John Kerry said early Friday.
A meeting of the International Syria Support Group in Munich resulted in a further agreement to "accelerate and expand" delivery of humanitarian aid as early as Monday, Kerry said.
Kerry, Russian Foreign Minister Sergei Lavrov and UN envoy Staffan de Mistura had held nearly six hours of negotiations with European and Middle Eastern foreign ministers before the cessation of hostilities was announced, hours before the Munich Security Conference.
The diplomats had met to push for a breakthrough ahead of peace talks scheduled to resume February 26 in Geneva.
The top diplomats of Iran and Saudi Arabia - regional powers considered key to any durable ceasefire and political transition in Syria - attended the talks. It was their first meeting since the countries broke off diplomatic relations in early January.
Hostilities on the ground in Syria had intensified in recent days, ahead of the talks.