Russia's gas transit to its European clients via Ukraine was blocked just hours after it was resumed Tuesday morning, Xinhua reports citing local media.    

Russian energy giant Gazprom started pumping gas to Europe Tuesday morning with observers from the European Union (EU) monitoring the process at a cross-border gas distribution station.

Ukraine "blocked all our actions" and Gazprom "have no physical opportunity to effect gas transportation through the Ukrainian territory," said deputy chairman of Gazprom's board Alexander Medvedev.

Russian gas has reached at the Sudzha gas station and the pressure in the pipeline is rising, Itar-Tass and Interfax cited one of the observers as saying.

 "However, gas spending at the entry to the Ukrainian gas transportation system is zero. This means Ukraine's entry taps are shut," the source said.

Russia cut off gas supplies to Ukraine on Jan. 1 after the two sides failed to reach a new deal for 2009 and resolve debt issues. Tensions were built up when Russia shut off all gas supplies to Europe via Ukraine on Jan. 7, accusing Ukraine of stealing gas.

Ukraine on Monday signed a new deal on monitoring Russian gas transit to Europe, removing conditions that Russia had opposed and clearing the final obstacle for Russia to resume gas supplies to Europe. //01.13.09