France is preparing for temperatures of 4 degrees Celsius (7.2 degrees Fahrenheit) above pre-industrial levels in the country by century's end as the world falls short in meeting climate change targets, a cabinet minister warned Sunday.

Christophe Bechu, minister for ecological transition, told the weekly JDD paper that his government was no longer banking on limiting the increase to 1.5 Celsius or at least well below 2.0 Celsius as agreed in the landmark 2015 Paris climate treaty.

Instead, the most optimistic scenario for 2100 was now 2 degrees for metropolitan France, but twice that was more likely.

"Unless all the world's states intensify their efforts to cut emissions further still, we are on track for global warming of between +2.8 and +3.2 degrees on average, which means +4 degrees for France because Europe is warming fast," Bechu said.

The government was calling that scenario "pessimistic". But Bechu said "in truth we should call it realistic", and that French efforts at adaptation should be based on the 4 degrees outlook, which France should prepare for.

Bechu is set on Tuesday to launch a public consultation to help define the French government's climate change roadmap and strategy for adaptation, as well as outline further efforts at greenhouse gas reduction.

"We can't escape the global reality of global warming," the minister said in a statement, also published Sunday.

"We will therefore have to prepare concretely for its unavoidable effects on our country and our lives," the statement said. "This is why we want to give our country a clear adaptation trajectory."

Last year was the hottest year on record in France, with records going back to 1900.

Bechu said France could face heatwaves lasting two months at a time if temperatures rise by 4 degrees, and some southern parts of the country might see up to 90 nights per year with sweltering tropical temperatures.

Droughts and extreme rainfall would also become commonplace.

© Agence France-Presse