German industrial and engineering conglomerate Siemens is to withdraw entirely from the nuclear industry.
The move is a response to the Fukushima nuclear disaster in Japan in March, chief executive Peter Loescher said.
He told Spiegel magazine it was the firm's answer to "the clear positioning of German society and politics for a pullout from nuclear energy".
"The chapter for us is closed," he said, announcing that the firm will no longer build nuclear power stations.
A long-planned joint venture with Russian nuclear firm Rosatom would also be cancelled, although Mr Loescher said he would still seek to work with their partner "in other fields".
Siemens was responsible for building all 17 of Germany's existing nuclear power plants, according to industry body, the World Nuclear Association.
Mr Loescher said Siemens would still make components, such as steam turbines, used in the conventional power industry that can also be used in nuclear plants.
He also gave his backing to the German government's planned switch to renewable energy sources, calling it a "project of the century" and claiming Berlin's target of reaching 35% renewable energy by 2020 was achievable.
U-turn
The German chancellor, Angela Merkel, announced at the end of May that all of the country's 17 nuclear reactors would be shut down by 2022.
Before the Fukushima disaster, nuclear power accounted for 23% of electricity production in Germany.
The German government's decision marked a complete U-turn by the chancellor, who only in September 2010 had announced that the life of existing nuclear plants would be extended by an average of 12 years.
Siemen's move, announced on Sunday, is also a turnaround.
In 2009, the firm withdrew from an eight-year-old nuclear joint venture with French energy firm Areva, because the German firm had ambitions to expand its own competence to build entire nuclear plants.
"In view of global climate change and the increasing power demand worldwide, for us nuclear energy remains an essential part of a sustainable energy mix," Mr Loescher had said at the time.