The U.S. envoy to the U.N. has condemned the reported cease-fire violations in southern Syria.
In a statement Friday, Ambassador Nikki Haley said "The Syrian regime's violations ?of the ceasefire in southwest Syria need to stop. We expect Russia ... to use the influence it has to stop the Syrian regime's violations and any further destabilizing actions in the southwest and throughout Syria.
"Russia will ultimately bear responsibility for any further escalations in ?Syria," added Haley.
The statement said the U.S. had negotiated southwest area de-escalation ceasefire with Russia "to de-escalate the conflict, save lives, create conditions for the safe and voluntary return of the displaced, and ultimately to move toward a peaceful political settlement in accordance with UN Security Council Resolution 2254."
Syrian President Bashar Assad has told a Russian television station that he thinks it would be pointless to have talks with the United States.
Fragments of the interview with the NTV station appeared on a messaging app site of Assad's office, Russian state news agency Tass reported Friday.
In it, Assad said "Negotiations with the U.S. now will not lead to anything, it's an empty waste of time. We are not going to talk to Americans just because they are Americans."
"We are ready to talk to anyone with whom we can achieve results, but we consider that U.S. policy will not change in the future," he was quoted as saying.
Syrian activists say government forces are keeping up their pressure on the country's strategic southwest, using artillery, airstrikes and barrel bombs to target rebel-held parts of the region.
The Britain-based Syrian Observatory for Human Rights says government helicopters have dropped more than 12 barrel bombs in the province of Daraa so far on Friday. It's the first use of the rudimentary and non-discriminatory weapons in the region in over a year.
Last July, the United States, Russia and Jordan negotiated a truce for the region, which borders Jordan and the Israeli-occupied Golan Heights.
The calm began to unravel in recent weeks, prompting U.S warning of "serious repercussions" for truce violations. Washington didn't elaborate.
The Observatory said 16 people have been killed in government strikes since Tuesday, including nine children.
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