Britain is preparing for possible power cuts by stocking up on portable generators and flashlights as well as winter clothes, thermal underwear and candles, Reuters reports.

Earlier, National Grid warned that Britain could face a three-hour scheduled blackout this winter if it cannot import power from Europe and tries to attract enough imports to fuel gas-fired power plants.

A comparison of data for the first 11 days of October 2021 with the same period this year showed a 203 percent increase in generator sales and a 43 percent increase in lantern sales, according to Toolstation, part of Travis Perkins, Britain's largest building materials retailer.

While it's far from certain that the National Grid will have to resort to a blackout this winter, it's clear that customers are preparing for this worst-case scenario, said a Toolstation spokesman.

Toolstation's data are consistent with a report this week by market researcher Kantar, which said Britons are stocking up on candles and blankets.

Department store chain John Lewis said last week that people are buying thermal underwear, gloves and bathrobes.

Energy regulator Ofgem said that British households should cut their gas and electricity consumption as much as possible this winter to reduce costs and the risk of blackouts.