Temperatures plunged to new lows in Europe where a week-long cold snap has now claimed more than 200 lives as forecasters warned that the big freeze would tighten its grip at the weekend, AFP news agency reported.

In the Czech Republic, the mercury dropped to as low as minus 38.1 degrees Celsius overnight while even Rome was sprinkled in snow.

In the last seven days, a total of 218 people have died from the cold weather, according to an AFP tally.

Ukraine's emergencies ministry said that the cold snap had now claimed 101 lives, substantially raising the previous toll of 63. Sixty-four of the victims died on the streets, it added.

Almost 1,600 people have requested medical attention for frostbite and hypothermia.

As they try to prevent the toll from rising even further, authorities announced that 2,940 shelters had been set up across the country where people could find warmth and food and another 100 would be opened in the next hours.

However there was no sign of an immediate let-up, with forecasters saying temperatures would hover between minus 25 to 30 degrees Celsius at night and minus 16 to 21 in the day.

The ferocious temperatures killed eight more people over the last 24 hours in Poland, bringing the death toll to 37, since the deep freeze began a week ago, police said.

Temperatures plunged to as low as minus 35 degrees Celsius in parts of Poland - but even that was three degrees warmer than the temperatures in the southwestern Sumava region of the Czech Republic.

Temperatures have been so cold in Bulgaria that parts of the River Danube have been frozen over.

Sixty percent of the surface near the port of Ruse was iced over, severely hindering navigation, the Danube exploration agency said.

Elsewhere in Bulgaria, another six people were found dead from the cold, bringing the overall tally to 16 in the last week, according to a tally of local media. No official figures have been released.

Most of the dead in the European Union's poorest country were people in villages, found frozen to death on the side of the road or in their unheated homes, the reports said.

More than 1,000 Bulgarian schools remained closed for a third day Friday amid fresh snowfalls and piercing winds in the northeast of the country.

Residents in Rome experienced only their second day of snow in the last 15 years. Up to five centimetres of snow fell in suburbs of the Italian capital, although there was little precipitation in the city centre.

Temperatures in the Alpine region of Piedmont in northern Italy went as low as minus 30 degrees Celsius.

The interior ministry advised car drivers to avoid regions of central Italy due to the heavy snowfall and traffic was backed up on some motorways.

However trains resumed normal service across the country except in and around Bologna and on a local line near Rome, the state railways said in a statement after days of delays that affected thousands of passengers.

Three people have died due to the extreme weather in recent days, including a homeless man found in the centre of Milan on Thursday.

Snow and freezing temperatures are forecast to continue into Saturday.

Swathes of Britain were bracing for snow after temperatures plunged to minus 11 degrees Celsius overnight in Chesham, southeast England.

Forecasters said many parts of the country would see several centimetres of snow, although it was likely to be powdery and would melt before long.

The Met Office said there was a danger that the cold weather would catch people off-guard after the warmer-than-normal winter so far.

"This weather could increase the health risks to vulnerable patients and disrupt the delivery of services," a spokesman said.

Bright winter sunshine bathed two thirds of France, bringing a note of cheer.

But around a third of the country, mainly in the east and centre, remained exposed to biting winds from the Baltic region, with an alert in place for low temperatures.

The French have cranked up their heating systems, and on Monday are expected to break an all time power consumption record set in 2010.

In Brittany and on the Cote d'Azur, where the French power grid is least efficient, consumers have been asked to turn off appliances for at least four hours per day to avoid blackouts.