German Environment Minister Peter Altmaier said his country would never again return to nuclear energy, hitting back at a top EU official who doubted Berlin’s commitment to phase out nuclear power.

“I cannot see any plausible political line-up that would enable a revival of nuclear power in Germany,” Altmaier told Friday’s edition of the Leipziger Volkszeitung regional daily.

After the 2011 Fukushima disaster in Japan, Germany embarked on an ambitious “energy revolution”, deciding to phase out its nuclear power plants by the end of 2022 and bolster renewable sources of energy such as solar and wind power.

However, concerns have mounted that this would entail a sharp rise in electricity prices amid difficulties in building a network able to transmit energy from the North Sea coast to the energy-hungry south of the country.

The European Union’s Energy Commissioner, Guenther Oettinger, told Monday’s edition of the Rheinische Post regional daily that there would “still be nuclear power on the German network in 40 years.”  He said there were still 140 nuclear power stations in Europe and that nuclear fusion technology was progressing rapidly. “Maybe this technology will one day be accepted in Germany,” said Oettinger, himself German.

Altmaier also vowed to find a permanent national storage site for nuclear waste by 2030. “We are together looking country-wide,” he said, adding that the search would be accelerated in the coming years.

The search would be “co-financed and jointly carried out” by Germany’s nuclear energy companies, he said.