Russia has had wild temperature swings this winter with an unusually balmy 9.5 degrees Celsius (49.1 degrees Fahrenheit) in the north-western city of Kaliningrad, a record, and -56 degrees in Siberia on Wednesday.

"The start of winter in Kaliningrad was unusually warm. On January 2, the temperature stood at 9.5 degrees Celsius, a record for January since the start of meteorological data," the local weather office said.

The pattern was set to continue this week, it said.

The Gulf of Finland off the port of Saint Petersburg did not freeze this year until January 9, a 100-year record, the ministry of emergency situations said.

But eastern Siberia was freezing.

"In Yakutia we recorded -56 degrees Celsius and -40 in the Far East," Itar-Tass news agency quoted local meteorological offices as saying.