Russia has fully resumed gas supplies to European Union (EU) countries, Wolfgang Ruttensdorfer, chief of Austria's biggest oil company OMV, confirmed on Monday.

Ruttensdorfer said Russia's state-controlled Gazprom has restarted gas supplies to its EU consumers from its newly established wells in the region bordering Ukraine, which are believed to hold a potential 95 million cubic meters of gas.

Gazprom cut off gas supplies to Ukraine on Sunday after Kiev rejected Moscow's demand for a sharp rise in gas prices starting from 2006. Russia's gas supplies to some EU countries were immediately affected.

Approximately 25 percent of the gas consumed in the EU is imported from Russia, and most of that is sent through pipelines which cross Ukraine.

On Monday, senior diplomats from Austria, which currently holdsthe EU's rotating presidency, summoned Russian and Ukranian diplomats to express the bloc's concern about the Russia-Ukraine gas dispute.