Millions of people across France woke up drenched in sweat on Tuesday after another night of scorching heat, with most of the population exposed to extreme and exceptional temperatures.

More than half of France's regions are under a red heat alert, as the country braces for sweltering temperatures in an intensifying heatwave.

In the south-west Gironde region, local authorities on Sunday said three people - aged between 80 and 95 years - had died, partly due to the intense heat.