Temperatures set to cross 40C as European heatwave kills three in France

People walk along the banks of the Seine River in Paris, France, during a heatwave. Photo: Reuters

Extreme heat has killed three people in France, and almost 2,700 French schools have shut or cut timetables as heatwave warnings spread across Europe.

Temperatures in Bordeaux were forecast to cross 42C on Monday, with 49 French regions placed under a red alert.

"We don't know when temperatures will start falling," French Health Minister Stephanie Rist said on TF1.

Three elderly people, aged 80 to 95, died over the weekend near Bordeaux from heat-related health issues, a local official said.

In Spain, a red alert was issued for the Basque Country, where San Sebastián was forecast to reach 40C — hotter than southern cities like Seville, which usually sees Spain's worst heat.

Nights have brought little relief in parts of Spain, with temperatures staying above 25C in some areas.

Europe's average high of 24C on Monday was 4.1C above the historic norm, the Reuters Climate Monitor showed.

Wildlife shelters in Belgium have also been overwhelmed, taking in 150 heat-affected birds in three days, said biologist Romaine de Jaegere.

Spain's Labour Ministry said it was checking whether firms were complying with rules allowing staff to adjust their hours or take paid leave during red weather alerts.