The heatwave scorching Europe has the fingerprints of climate change all over it and is "the latest price to pay for fossil fuel pollution baking our planet", UN climate chief Simon Stiell said Thursday.

Europe has endured extreme heat this week, with record-breaking temperatures in France, Britain and Spain and other countries issuing high-level heat alerts.

"Europe's savage heatwave has the fingerprints of the climate crisis all over it –- it's the latest price to pay for fossil fuel pollution baking our planet," Stiell said in a statement.

"Until humanity stops burning colossal amounts of coal, oil and gas, extreme heat will keep getting worse," he said.