Authorities have searched the homes and workplaces of the two suspects, who are accused of working for a foreign secret service, the prosecutor's office said in a statement.
One of the suspects, identified as Dieter S., had since October 2023 discussed possible plots with a person linked to the Russian secret service, the statement said.
Dieter S. had been prepared to carry out bomb and arson attacks on military facilities, including those operated by U.S. forces, the statement said.
According to Spiegel magazine, the facilities included the Grafenwoehr army base in the southern state of Bavaria where Ukrainian soldiers receive training to use U.S. Abrams tanks.
The Russian embassy in Berlin did not immediately respond to a request for comment.
"The actions were intended in particular to undermine the military support provided by Germany to Ukraine against the Russian war of aggression," the statement by German prosecutors said.
(Reporting by Andrey Sychev and Alexander Ratz Writing by Rachel More and Matthias Williams Editing by Madeline Chambers)
