Europe's bitterly cold weather has killed another 33 people, and melting snow caused a dam wall to break and flood a village in Bulgaria.

Four people drowned when the dam flooded the village of Bisser, in southern Bulgaria, after heavy rain and snow melting. Four more people died in Bulgarian floods when their cars were swept away by high waters.

"There are demolished houses and people in distress," the interior ministry said. Bulgaria warned neighbouring Greece and Turkey that two other dams were expected to overflow later on Monday.

Gas supplies to the European Union from Russia improved at the weekend but had not fully recovered, the European commission said, as Italy convened a crisis committee to handle what it called critical shortages of Russian gas.

Nine more people died in Poland, bringing the total to 62 since the end of January. Temperatures fell to -24C at night in north-eastern parts of the country.

In Croatia's Dalmatia region, more than 100 villages were cut off by snow, but rescuers reached some people on Sunday. In one village, a woman gave birth in her house with the help of a neighbour while a midwife from a nearby town gave them instructions by telephone. "The baby girl is fine and beautiful and I'll probably name her Snow White, given the circumstances," the mother, Marta Glavota, told the 24sata news website.