Oslo - A mechanism to safeguard sufficient hydropower supply in Norway, which could ultimately curb power exports, will likely come in the spring, its oil and energy minister told Reuters on Thursday.

Norway said in August it could restrict power exports if water reservoir levels fall towards critically low levels, which attracted criticism from fellow Nordic countries, which rely on Norwegian power for some of their demand.

The government still plans to propose measures to ensure security of supplies, which could involve export restrictions, but they would not come into effect this winter, when power demand peaks, said Oil and Energy Minister Terje Aasland.

"What is important... is to have it in place before the snow melt (in May-July), so we have it for the new hydropower season," he said in an interview on the sidelines of an energy conference.

Norway, which depends on hydropower for more than 90% of its electricity production, in August marked the driest 12-month period in 26 years in southern Norway, with reservoirs falling to record low levels and sending prices up.

Filling levels in the region, however, have improved over the past weeks, amid wet weather and lower power generation as producers conserve water for winter production.

"And now that we have had more precipitation, we can be confident and say quite safely that the danger of (power) rationing this winter is low," Aasland added.

Norway exports electricity via cross border connections, including subsea cables, to Sweden, Denmark, Germany, Britain and the Netherlands.

(Reporting by Nora Buli; Editing by Gwladys Fouche and Mark Potter)