France faced unusually hot weather on Monday, the national weather service said, after enduring record high temperatures for a month of May at the weekend.

In the northwestern city of Rennes, 74-year-old Daniele Dupont tried to stick to the shade as she walked her dog in 27C on Monday morning

"I'm going to close the shutters. I won't be going out this afternoon," she said in the capital of the Brittany region, across the Channel from the United Kingdom.

Parts of Brittany were under a so-called yellow heatwave alert, urging caution, for a second day on Monday.

A Meteo France spokeswoman told AFP that the warning first issued for Sunday was "the first yellow heatwave alert to be issued in May since the system was created in 2004".