The U.S called late on Monday an urgent meeting in Jordan out of concern after reports were released of strikes in southwestern Syria within the boundaries of the de-escalation zone.

A a US State Department official said in a statement, that if the reports were true, they would be a clear violation by the Syrian government.
"We urge all parties in the southwest de-escalation zone not to take actions that would jeopardize the ceasefire and make future cooperation more difficult," the statement said.

"We have called an urgent meeting in Jordan to review the situation in southwest Syria and ensure maintenance of the de-escalation zone that the United States helped negotiate," the statement added.

Earlier in September, Russia, Turkey and Iran agreed to set up de-escalation zones in Syria for six months, where Eastern Ghouta, Idlib, Homs, Latakia, Aleppo and Hama were included. The agreement also stated that the six-month term may be extended.