Syrian government helicopters dropped barrel bombs on opposition areas of the country's southwest on Friday for the first time in a year, a war monitor and rebel officials said, in defiance of U.S. demands that President Bashar Assad halt the assault.
Assad has sworn to recapture the area bordering Jordan and the Israeli-occupied Golan Heights. The army this past week began ramping up an assault there, threatening a "de-escalation" zone that was agreed upon by the United States and Russia last year.
The United States on Thursday reiterated its demand that the zone be respected, warning Assad and his Russian allies of "serious repercussions" of violations. It accused Damascus of initiating airstrikes, artillery and rocket attacks.