What has being called a - regime of calm - is now underway in Syria.
It follows a series of airstrikes on medical facilities this week in the city of Aleppo.
Dozens of people including the area's last paediatric doctor were killed in the attacks.
However the city has been excluded from a truce which kicked into action in two areas - in the early hours of this morning.
White House spokesperson Josh Earnest has said it is back to the drawing board for the war torn country: “We acknowledged all along that there were likely to be violations over the cessation of hostilities but what has happened over the past week or so, the frequency of violations has increased and that has been the source of significant concern.
“So our hope is by refreshing this agreement, we can build momentum towards a broadly observed cessation of hostilities.”