Yes. I can just imagine Lavrov calling Tillerson and telling him, "By the way, we have set up a new deconfliction zone where anything that doesn't have the explicit permission of the Syrian government gets shot down.A comment more insightful than it seems on its face. The U.S. has declared the area around al-Tanf in southern Syria a "deconfliction" zone but neither Syria nor Russia agreed to what was a unilateral declaration by the U.S. There is no such deconfliction zone in southern Syria.
"It's called 'Syria'".
 Comment by Tom on "Russia and US in suspected deal in southern Syria." By Adam Garrie, The Duran, 6/10/17.
 "Lavrov Confirms Pentagon Is Lying. There Are No Agreed-Upon 'De-Confliction Zones' in Syria." By Marko Marjanović, Russia Insider 6/7/17.