Russia reinforces warship numbers off Syria coast 'to back imminent Idlib offensive'

Russia has moved the largest number of warships towards the Syria coast since it entered the Syrian conflict amid growing speculation of an imminent offensive on rebel-held Idlib province.

Pro-Kremlin paper Izvestia reported on Tuesday that the buildup was the biggest naval task force deployed to the Mediterranean Sea since the start of Russia's intervention in Syria in 2015.

The report said 10 wars ships equipped with 'Kalibr' cruise missiles and two submarines are Syrian waters with "several more" on the way.

"The group was sent to sea to support the offensive of the Syrian army in the province of Idlib," the report said, citing military experts.

A Syrian regime spokesman told the newspaper that the Russian warships was "important to prevent Western countries from hindering the speedy conclusion of the war".

The Kommersant daily reported that Russia sent two warships and an additional anti-aircraft missile system to the Mediterranean in August, quoting anonymous sources.

On Wednesday, NATO confirmed a large-scale Russian navy buildup and urged Moscow to "exercise restraint and refrain from worsening an already disastrous humanitarian situation".

"The Russian Navy has dispatched substantial naval forces to the Mediterranean, including several ships equipped with modern cruise missiles," a NATO spokesperson told Israeli daily Haaretz.

Syria's regime is gearing up for an expected offensive in Idlib province, which is home to nearly 3 million people in addition to Syrian rebel groups.

It borders Turkey, which fears an offensive may trigger a humanitarian and security catastrophe.

The UN's director of humanitarian operations warned on Tuesday that a large-scale offensive on Idlib "has the potential to create a humanitarian emergency at a scale not yet seen" in the seven-year civil war.