France derives the vast share of its electric power from nuclear plants and sees atomic energy as key to transitioning away from fossil fuels.

But Germany, after the Fukushima nuclear disaster, has turned its back on nuclear energy and is the continent's strongest promoter of natural gas as the right alternative to coal and other fossil fuels.

"Either we fight climate change with an ideological approach and we will fail, or we fight climate change with a scientific approach and then we will succeed. But this means recognising the added value of nuclear energy," said Le Maire at a press conference in Slovenia.

Le Maire was speaking on the sidelines of an EU finance ministers meeting at Brdo Castle in Slovenia, which holds the rotating presidency of the European Union.

At issue is the so-called "green taxonomy" classification system that will define what constitutes sustainable investment as the EU moves towards carbon neutrality by 2050.

Due by the end of the year, this classification will open up access to green finance and give a competitive advantage to recognised sectors.

The subject divides the member states: while France, Poland and the Czech Republic defend the atom, countries such as Germany and Austria are fiercely opposed to it, as are many NGOs which see it as a risky technology.

"I just want to remind the other member states and European citizens that two expert reports have come to the same conclusion, namely that nuclear energy is necessary to fight climate change," Le Maire said.

In June 2019, a group of experts on sustainable finance concluded that nuclear energy, which emits virtually no CO2, could "help mitigate climate change" - but without concluding on its potential environmental damage.

Then in a report issued at the end of March, the European Commission's scientific service found that "no analysis provides scientific evidence that nuclear energy harms human health or the environment more than other energies" that could be included in the taxonomy.

"This means that nuclear energy should be included in the European taxonomy. There is no reason why nuclear energy should not be included in the European taxonomy by the end of the year," Le Maire insisted.