The governor, wearing one herself under a jacket, encouraged residents to don turtleneck jumpers both to stay warm and as a way of reducing energy consumption.“Warming the neck has a thermal effect. I’m wearing a turtleneck myself and wearing a scarf also keeps you warm. This will save electricity,” Koike told reporters on Friday.

“This is one of the tools to get through the harsh winter energy climate together,” she said, adding that French President Emmanuel Macron was “taking a lead in wearing turtlenecks.”