"If we see that our Ukrainian partners-as in 2008- start siphoning off our gas from the export pipeline system in an unauthorized manner then we will also - like in 2008- be gradually reducing supplies by the amount that has been stolen," Vladimir Putin told reporters on a visit to Belgrade.

The Russian president, who is on his way to Milan to meet EU officials and Ukrainian President Petro Poroshenko, confirmed that "there will be no crises through a fault of Russian participants of energy cooperation in Europe."

Russian gas exporter Gazprom nearly doubled gas prices to Ukraine last April, a few weeks after former President and close ally of Russia, Victor Yanukovych, was ousted. The Kremlin cut off supplies this year in June after Kiev refused to pay the higher rate. Russia then expressed a fear that Ukraine may begin to siphon off gas flowing through its country into Europe this winter.

Putin called this problem a "transit risk" and said that if Ukraine would remove gas from the pipeline without permission, then Kremlin would try and recover the costs by stopping any further supply of gas through Ukraine.

Arguments over gas pricing are a common affair between Russia and Ukraine. Gazprom cut off gas to Ukraine in the winters of 2005-2006 and 2008-2009. Supplies to European customers were consequently disrupted.

European Union, Russian and Ukrainian leaders are scheduled to meet exclusively for a discussion the gas conflict on October 21 in Berlin.

mg/es (AFP, Reuters)