German Chancellor Olaf Scholz on Wednesday raised the possibility of keeping nuclear plants going as he accused Russia of blocking the delivery of a key turbine to throttle gas supplies to Europe.
The continent's biggest economy has been scrambling for energy sources to fill a gap left by a reduction in gas supplies from Moscow.
The power stations, which are set to be taken off the grid at the end of the year, were "relevant exclusively for electricity production, and only for a small part of it", Scholz said.
In total, the nuclear fleet accounts for six percent of Germany's electricity output.
The government has said it will await the outcome of a new "stress test" of the national electric grid before determining whether to stick with the long-planned phase-out.
- Nuclear switch -
Former chancellor Angela Merkel spectacularly decided to ditch atomic energy in 2011 following the Fukushima nuclear disaster in Japan.
Germany has already moved to restart mothballed coal power plants to guard against an energy shortfall.
The squeeze comes as Russia dwindles supplies of gas, which Germany has long relied on to power industry and heat homes.
Russian energy giant Gazprom has chalked up limited supplies to technical issues.
The delayed return of a turbine from Canada, where the unit was being serviced, was behind the initial reduction in deliveries via the Nord Stream 1 gas pipeline in June, according to Gazprom.
Supplies via the energy link were further reduced to around 20 percent of capacity in late July, after Gazprom halted the operation of one of the last two operating turbines due to the "technical condition of the engine".
- Turbine trouble -
Berlin has dismissed Gazprom's justifications for the reduction to supply, seeing instead a "political" move in response to the West's support for Ukraine.
The turbine which was transferred from Canada to Germany was "available and working", Scholz said Wednesday.
"There is no reason why this delivery cannot happen," he said, adding that it had received "all the approvals" needed for export from Germany to Russia.
Pipeline operators only had to say "they want to have the turbine and provide the necessary customs information for transport to Russia", Scholz said.
Gazprom however insisted it was unable to take delivery of the turbine.
"Sanctions regimes in Canada, in the European Union and in Britain, as well as the inconsistencies in the current situation concerning the contractual obligations of (turbine maker) Siemens make the delivery impossible," it said.
Kremlin spokesman Dmitry Peskov also said Gazprom was still waiting for documents confirming the unit was "not affected by sanctions".
It was however "technologically possible" in the opinion of Russian President Vladimir Putin to continue deliveries via the Nord Stream 2 pipeline, Peskov said.
The second pipeline, which runs parallel to Nord Stream 1, stands completed but was blocked by the German government in the run-up to the invasion of Ukraine.
Former chancellor Gerhard Schroeder, who signed off on the pipeline while in office, told German magazine Stern it was "the easiest solution" to use Nord Stream 2 instead.
But Scholz has rejected the call, saying Nord Stream 1 provided sufficient capacity for gas flows.
Moscow's move to limit supplies sent a "difficult message" to the world by creating doubt over Russia's commitment to its agreements, he added.