The Eurasia Group report said: “Friday’s series of escalatory actions bring US-Russian relations to their lowest level since Moscow used force in Ukraine in 2014.
“Developments pose risk of a cyber-war, additional US sanctions, increasingly provocative military postures, and diplomatic expulsions.
“Sanctions against people and firms involved in cyber or Syria (Aleppo) are likely.
“Possible but less likely is a relatively minor cyber-attack against a Russian individual or firm, one that may never become public.
“Impact here would be high, but the risk of an escalating cyber war will probably lead the Obama team to step back from even a limited attack on Russian Internet or critical infrastructure.”