( CNN) After six years of war, over 500, 000 people killed, millions more displaced and chemical weapons now the norm, the world's two most powerful leaders — US President Donald Trump and Russian President Vladimir Putin — agreed to a ceasefire in Southern Syria two weeks ago.

The only way to ensure any longevity in this ceasefire is to ensure the UN has a central role.

This will only happen if the five permanent members of the Security Council — the US, Russia, China, France and the UK — come together to give the UN the authority to monitor the ceasefire and deliver both aid and reconstruction.

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