Two brand new diesel-electric submarines, said to be the quietest in their class, have arrived in the Mediterranean to support the Black Sea Fleet’s task force operating off the coast of Syria, the Russian Navy has said.

Non-nuclear submarines , the ‘Kolpino’ and the ‘Velikiy Novgorod’, built in Saint Petersburg and named after two Russian cities, set sail from the Baltic Sea earlier in August.

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“Two newest diesel-electric submarines of the Black Sea Fleet – the ‘Kolpino’ and the ‘Velikiy Novgorod’ – have arrived in the Mediterranean from the Baltic Sea,” spokesman for the Black Sea Fleet Captain Vyacheslav Trukhachev told RIA Novosti on Monday.

The submarines will join the standing naval task force in the Mediterranean, the officer said without elaborating on the issue.

The ‘Kolpino’ and the ‘Velikiy Novgorod’, designated ‘Project 636.3’ in Russia and ‘Improved Kilo class’ in the West, were commissioned by the Saint-Petersburg Admiralty Shipyard for the Black Sea Fleet earlier this year.

The cutting edge attack submarines are mainly designed for anti-ship and anti-submarine warfare in shallow waters. According to open sources, the subs feature upgraded sonar systems and 533mm torpedoes. They can also lay mines, and fire Kalibr-NK cruise missiles from torpedo tubes.

Submarines of the Improved Kilo class have gained popularity among world navies due to their enhanced stealth capabilities and a design that has proved effective over time.

Around 28 submarines are in use with the Russian Navy, with a further six due to enter service over the next few years. India operates ten submarines of the Kilo class, designated in that country as ‘Sindhughosh class’. Vietnam, with six Russian-built subs, is the third-largest operator.

Russia has maintained a naval group in the Mediterranean since the very start of its anti-terrorism operation in Syria. The task force comprises Russia’s newest warships and a number of auxiliary vessels.

Earlier in June, the Black Sea Fleet said it had dispatched fifteen warships, including the frigates ‘Admiral Grigorovich’ and ‘Admiral Essen’, as well as the corvette ‘Smetlivy’ and the submarine ‘Krasnodar’.

Three large landing craft – the ‘Caesar Kunikov’, the ‘Nikolay Filchenkov’ and the ‘Azov’ – as well as mine-sweepers, counter-insurgency boats and a tanker, are assigned to the Mediterranean task force.

Last November, the task force reached its peak in terms of combat capabilities when the Russian aircraft carrier ‘Admiral Kuznetsov’ arrived in the region after a weeks-long journey from its base with the Northern Fleet.