The US Federal Aviation Administration (FAA) has restricted US operators from flying in the Damascus flight information region, which includes the whole of Syria.
The FAA issued a new notice to airmen (NOTAM), barring them to fly over these regions.
This restriction comes in place of the previous NOTAM, which had different guidelines for flying in this airspace. According to the previous NOTAM, US operators were advised against flying over these regions. However, they could do that by contacting FAA before operating there.
The FAA statement stated that this restriction was based on an updated assessment of the risk associated with such operations. It also said that there was also a lack of any requests from operators wishing to fly over the region, which initiated the ban.
The statement further stated: "The ongoing armed conflict and volatile security environment in Syria poses a serious potential threat to civil aviation. Armed extremist groups in Syria are known to be equipped with a variety of anti-aircraft weapons, which have the capability to threaten civilian aircraft.
"Opposition groups have successfully shot down Syrian military aircraft using these anti-aircraft weapon systems during the course of the conflict. Opposition elements have previously warned civilian air carriers against providing service to Syria.
"Due to the presence of anti-aircraft weapons among the extremist groups and ongoing fighting in various locations throughout Syria, there is a continuing significant potential threat to civil aviation operating in Syrian airspace."
This NOTAM would apply to all US air carriers and commercial operators, as well as anyone exercising the privileges of an airman certificate that has been issued by the FAA, except those who are operating US-registered aircraft for foreign air carriers.