Heavy snow blanketed Romania and Bulgaria on Thursday, cutting power to hundreds of towns and villages, blocking roads and forcing Bucharest's two airports and some Black Sea ports to close.

Meteorologists said the snow, which had been falling for two days, was expected to continue throughout Romania until late on Thursday, with temperatures expected to fall as low as minus 16 degrees Celsius (3 degrees Fahrenheit).

After that, further snow was forecast only for the south.

The customs post at Giurgiu on the Danube river border with Bulgaria was closed and the Foreign Ministry said 1,300 Romanian tourists were stranded in the neighboring country because of the weather.

In Bulgaria, two days of heavy snow and high winds cut electricity supplies to more than 300 towns and villages, the country's Disaster and Emergency Ministry said. More than 30 villages were without supplies of drinking water.

Several municipalities in northern and southern Bulgaria declared a state of emergency and the army was called in to help rescue stranded motorists and trucks and clear blocked roads.

In Romania, television showed traffic jams on snow-covered roads and blocked trains.

In Bucharest, the mayor appealed to residents to help to clear a layer of up to 50 cm (20 inches) of snow and use public transport rather than private cars.

(Reporting by Luiza Ilie in Bucharest and Anna Mudeva in Sofia; Editing by Andrew Dobbie)