European officials are urging Russia and Ukraine to quickly enforce an agreement to resume delivery of natural gas to many of the freezing nations affected by a dispute which has paralyzed supply delivery.

Millions of people are enduring heat and cooking gas shortages as well as sub-zero temperatures.

On Friday German Chancellor, Angela Merkel, is expected to meet for an emergency meeting in Berlin with Russian Prime Minister Vladimir Putin and his Ukrainian counterpart Yulia Timoshenko.

Merkel said she was likely to reinforce the EU's position as a natural gas customer.

There is a risk that the confidence in Russia may be lost due to the ongoing disruption, said Merkel, according to CNN.

European Commission President Jose Manuel Barroso on Thursday urged Ukraine and Russia to quickly implement a compromise that would return natural gas deliveries from Russia's Gazprom's pipelines through the Ukraine as soon as possible.

Ukraine is a major entry point for Russian gas into Europe. Russia and Ukraine's dispute over pricing and contractual terms began nearly a year ago, escalating into the present crisis that has prompted Russia to turn off its taps. Both nations help deliver about 25 percent of Europe's natural gas.

In the long term, the EU plans to seek alternative sources for gas supply.

It has already eyed plans to build a pipeline to purchase natural gas from Central Asia and eventually Iraq and Iran. It was also building up infrastructure to import liquefied gas from North Africa and the Middle East and exploring nuclear energy.

Russia Germany Vladimir putin Ukraine