Moscow - The Russian gas monopoly Gazprom began Tuesday to pump gas to Europe into a Ukrainian transit pipeline for the first time since a nearly two-week supply blockade began, the Russian Interfax news agency reported.

The supply resumed after both countries laid aside a bitter dispute over fees and the illegal siphoning of gas, which had cut European countries off from energy supplies in the middle of a harsh winter.

Ukraine said it would not obstruct the deliveries, but experts said even after the taps are reopened, it could take up to three days for gas flows to reach Europe and for pressure to return to normal in the pipelines.

The European Union has been hard hit by the gas row since Russia cut all supplies via Ukraine on January 7, accusing it of stealing gas transits.

Roughly one-quarter of all gas burned in the EU comes from Russia, and 80 per cent of it passes through Ukrainian pipelines.

Hundreds of thousands of people have been left without heating fuel, and factories and schools have been forced to close as sub-freezing temperature swept countries in Eastern Europe most severely affected by the gas cut-off. (dpa)