Shops in France have been told to keep their doors closed or face a £640 fine with new laws to be passed within days. Shops will have to comply with the rules when using air conditioning or heating.
They will also have to turn off lights between 1am and 6am in a bid to reduce energy use. Similar rules already apply in some parts of France and will now be rolled out nationwide, the country's Minister of Ecological Transition Agnes Pannier-Runacher told the Journal du Dimanche newspaper.
Ms Pannier-Runacher will issue two decrees on energy waste in the coming days. She said: "The first will widen the ban on illuminated advertising, whatever the size of the city, between 1am and 6am.
"The second will ban shops from having their doors open while the air conditioning and heating are working."
The neon sign ban currently applies o any town with a population under 800,000 people. It comes as energy company Shell has warned that rationing of power supplies cannot be ruled out.