The European Union will push its member countries to invest more in environmental management to reduce wildfire risk, the bloc's environment commissioner told Reuters on Thursday, as ​experts said the economic cost of this summer's blazes had already exceeded €15 billion.

Extreme ‌wildfires have ripped through France, Spain and Greece this summer, causing €15.6 billion to €19.1 billion in economic costs - including damage to property, infrastructure, firefighting costs, debris removal and anticipated insurance claims - according to estimates published by forecaster ​AccuWeather on Thursday.

Scientists have confirmed human-caused global warming made the extreme weather fuelling these fires more ​likely.

But the speed and severity with which the blazes spread have ⁠also raised questions about whether countries are investing enough in environmental management, such as by clearing ​forests of dry, flammable vegetation, and restoring wetlands that can act as natural firebreaks.

"Prevention is the ​first line of defence... it is obvious that we need to invest more in nature," EU environment commissioner Jessika Roswall said in an interview.