A Russian Sukhoi Su-35 bomber lands at the Russian Hmeymim military base in Latakia province, in the northwest of Syria on May 4, 2016. (AFP PHOTO)

MOSCOW, Sept. 5 (Xinhua) -- Four Russian jets of the Hmeymim airbase in Syria bombed positions of Nusra Front in Idlib province on Tuesday, the Russian Defense Ministry said Wednesday.

Two Su-34 fighter-bombers struck a precise blow to a workshop where Nusra Front fighters were assembling attack drones and a warehouse of explosives for the drones, the ministry's spokesman Igor Konashenkov said in a statement.

A Su-35S fighter destroyed with high-precision ammunition a warehouse of portable air defense systems, Konashenkov said.

All the attacks were carried out "exclusively on the objects of terrorist groups identified and confirmed through several channels and far from populated areas," he said.

Also on Tuesday, Russia destroyed two drones launched by militants to attack the Hmeymim airbase, raising the number of downed drones to 47 in a month, Konashenkov said.

Idlib, a city in northwestern Syria controlled by "ultra-radical groups" as Russia calls, has a population of about 2.5 million and is strategically important as it borders Turkey.

It is close to the coastal province of Latakia, home of Syrian President Bashar al-Assad, which also hosts the Russia-operated Hmeymim airbase.

The Syrian government army has been amassing forces and military gears around Idlib in recent weeks.

U.S. Secretary of State Mike Pompeo on Tuesday spoke with Turkish Foreign Minister Mevlut Cavusoglu by phone and agreed that Syria's possible offensive in Idlib is unacceptable.

Russia is conducting large-scale military drills in the Mediterranean on Sept. 1-8 involving more than 25 battleships and 30 warplanes.