THE PENTAGON — Armed Russian fighters have sortied from carrier Admiral Kuznetsov for flights over Syria ahead of an anticipated combined arms strike on rebels opposed to Bashar al-Assad near Aleppo, a U.S. defense official told USNI News on Tuesday.

While the fighters have not dropped ordnance in scouting out the approaches to Aleppo, signs point to the combination of Sukhoi Su-33s and Mikoyan MiG-29Ks as part of a larger force set to move on Aleppo as soon as this week, the official confirmed.

In a statement, the Pentagon chided Russian statement in the press telegraphing the impending assault on Aleppo but did not provide additional details.

“We are aware of reports that the Russian Federation is preparing to escalate their military campaign in Syria. The United States, time and again, has worked to try and de-escalate the violence in Syria and provide humanitarian aid to civilians suffering under siege,” read the statement on reports of impending Russian strikes provided to USNI News on Wednesday.

“Yet instead of joining us constructively to reach those goals, Russia has continued to back the Bashar al-Assad regime’s war against the Syrian people. The comments from the Russian Ministry of Defense suggest they are more interested in the world seeing Russia’s naval capabilities in action than the world seeing Russia live up to its word. An escalation would make it harder to resolve the brutal civil war in Syria and raise more doubts about Russia’s commitment to a political solution.”

Operating south of Cyprus, Kuznetsov is part of a surface action group — made up of the carrier Admiral Kuznetsov, cruiser Peter the Great and two Udaloy-class guided missile destroyers plus auxiliaries — the Russians moved into striking range of positions near Aleppo this week, officials told USNI News.

In addition to the quartet, the Russian Navy sortied the new frigate Admiral Grigorovich from the Black Sea in the region. Grigorovich is armed with Russian Kalibir NK long-range land attack cruise missiles – first used operationally last year in strikes in Syria from Russian patrol ships in the Caspian Sea.

Russia have operated strike fighters from bases in Syria for more than the last year and also established a healthy air defense network over their installations.

Relative to existing forces, the addition of the Russian ships bring little to the fight within the borders of Syria, the capabilities of the action group and coastal defense anti-ship missiles Russian forces have in the country could severely complicate operations of U.S. ships and aircraft operating in the Eastern Mediterranean, USNI News understands.