Russia has halted all gas supplies to European countries including Turkey and Greece. The move comes amid a deepening rift between Russia and Ukraine, which hosts a pipeline supplying gas from its bigger neighbour to countries across Europe.
Bulgaria and Macedonia also reported that all supplies of Russian gas had been cut, while Romania's pipeline operator said that its supplies had been cut by 75 per cent.
The European Commission condemned the cuts as "completely unacceptable". In an unusually strongly worded statement, it demanded that Russia restore supplies "immediately".
Russia ordered a reduction in gas flow to Europe via Ukraine on Monday, a measure it said was to stop its neighbour from stealing fuel. Ukraine said the move would jeopardise supplies to the rest of Europe, which is facing freezing temperatures.