France expects its plans for a €72bn ($84bn) expansion of its nuclear energy industry will be a “major contributor” to the EU’s electricity production, Paris said after the European Commission announced an “in-depth” state aid investigation into the project.

“France’s new nuclear energy sector will, in the coming years, be a major contributor to EU-generated electricity,” the French government said in a statement.

The commission said this week it had opened an in-depth investigation to assess whether public support that France plans to grant for the construction and operation of six new nuclear reactors is in line with EU state aid rules.