In case of extreme winter weather conditions, electricity-supply restrictions might be necessary, Ivan Ayolov, Electricity System Operator executive director said at a news conference.

Electricity-supply restrictions might be necessary because of insufficient coal reserves for the thermal power plants.

The shutting down of units three and four of Kozloduy nuclear power plant in December 2006 had reduced Bulgaria's electricity productivity.

Under normal weather circumstances, it would not be necessary to impose restrictions, Focus news agency quoted Ayolov as saying.

The National Electricity Company continued to export electricity to neighbouring countries, although export had been decreased to 52.7 per cent compared to 2006.