Updated

The Kremlin says Russian President Vladimir Putin has ordered a surprise military exercise in the Black Sea.

News agencies quoted his spokesman Dmitry Peskov as saying Putin dispatched the order to the defense minister at 4 a.m. on Thursday.

A Kremlin statement says the exercise will involve 36 vessels, an unspecified number of airplanes and up to 7,000 troops. Peskov says maneuvers involving fewer than 7,000 troops do not require approval from Russia's neighbors.

Peskov said ships taking part in the exercise have already left the Russia-leased Sevastopol port in Ukraine's Crimea peninsula.

Russia's naval affairs are under scrutiny due to the civil war in ally Syria. Russia risks losing access to its naval base in Syria's Tartus port on the Mediterranean Sea if the Syrian regime is toppled.