KIEV/BELGRADE - Record-low temperatures in parts of Eastern Europe pushed the death toll from Arctic conditions to at least 89 people on Wednesday, and have forced Russian gas provider Gazprom to warn over supplies to Europe.

Europe had enjoyed a relatively mild winter up until last weekend, but a Siberian system swinging in from the east brought that to an abrupt halt.

A woman out jogging wears warm winter clothes during a freezing cold afternoon in Zurich, February 1, 2012. The cold snap which has gripped Europe and killed?89 people in the east is set to lift European power and gas prices further as energy demand for heating surges while temperatures are expected to stay below freezing point. [Photo/Agencies]

A source at Russian gas export monopoly, which supplies a quarter of Europe's gas imports, said it was getting more requests from export markets than it could physically accommodate as demand from Russia spikes. ?

The company however sought to reassure clients on Wednesday. "Despite increasing gas consumption in Russia due to heavy frosts, Gazprom continues implementing its contractual obligations to European clients," it said in e-mailed comments. ?

In Ukraine, 43 people have died in the past five days, its emergency ministry said, as the country shivered through its coldest winter in six years. Overnight temperatures sank as low as minus 33 degrees Celsius (minus 27 Fahrenheit) and hundreds of heated tents have been put up to shelter the homeless. ?

"They say the whole February will be cold, and the first half of March, so we have to get ready for this somehow," said Viktor, who is living on the streets of Kiev.

European weather alert network Meteoalarm warned of "extremely dangerous" conditions in several parts of eastern Europe, including Serbia, where a fourth person was found dead overnight in the southwestern mountain areas.

Security forces there, and in neighbouring Bosnia, have used helicopters to ferry supplies to areas cut off by deep snow and to evacuate the elderly. The forecast across the Balkans is for conditions to worsen through the week.

Meteoalarm said severe cold was likely to persist in many parts of continental Europe including Germany and especially in southeastern Europe.