Washington, DC - Secretary of State John Kerry: "I am gratified to see the final arrangements concluded today for a cessation of hostilities in Syria and call on all parties to accept and fully comply with its terms. If implemented and adhered to, this cessation will not only lead to a decline in violence, but also continue to expand the delivery of urgently needed humanitarian supplies to besieged areas and support a political transition to a government that is responsive to the desires of the Syrian people.

"Today's agreement results from the committed diplomacy of many countries and groups, and I want to thank all those who worked diligently to bring it about, including the U.S. and Russian delegations and other members of the International Syria Support Group.

"We are all aware of the significant challenges ahead. Over the coming days, we will be working to secure commitments from key parties that they will abide by the terms of this cessation of hostilities and further develop modalities for monitoring and enforcement.

"This is a moment of promise, but the fulfillment of that promise depends on actions. All parties must meet their commitments under this agreement, ensure full implementation of UN Security Council Resolution 2254, and cease attacks on each other, including aerial bombardments. And all parties must remain committed over a period of time to make possible a political end to this conflict.

"As we move forward, we will remain vigilant to ensure that implementation achieves what we set out to do, which is to stop the violence and provide the space and the opportunity for a negotiated political transition, consistent with the Geneva Communique of 2012, that unites all Syrians who reject dictatorship and terrorism and want to build a new future for their country."