U.S.' Bolton: Russia missile sale to Syria is 'significant escalation'
![](https://r58b8e.a2cdn1.secureserver.net/wp-content/uploads/2018/02/worldnewsdyil2auoc8za.gif?time=1720120637)
U.S. National Security Adviser John Bolton said on Monday that Russian plans to supply Syria with a S-300 missile system would be a “significant escalation” by Moscow and hopes it will reconsider.