The leak was highlighted by lawmakers from the northeastern German federal state of Mecklenburg-Western Pomerania, Poland's biznesalert.pl website reported on Friday.
It said the state legislature was carrying out a probe into possible Russian influence over the government of Mecklenburg-Western Pomerania in connection with the controversial Nord Stream 2 project.
According to investigators, the Stralsund maritime authority mistakenly provided the Nord Stream 2 company, owned by Russia's Gazprom, with details of NATO manoeuvres in the Baltic Sea, biznesalert.pl reported.
A NATO exercise was set to take place near the projected route of the Nord Stream 2 pipeline, which was then in the planning phase, according to biznesalert.pl.
The probe established that German military authorities intervened to remove the sensitive NATO data from the dossier that had been shared with the Nord Stream 2 company.
The Stralsund office, however, in the meantime released the documentation to the public via the internet, biznesalert.pl reported.
Experts have warned that leaking sensitive data to Russian-owned companies could undermine the security of NATO allies.
The Nord Stream 2 pipeline was never launched due to the Kremlin's February 2022 invasion of Ukraine.
In September last year, the Russia-to-Germany Nord Stream 1 and 2 pipelines were damaged by explosions.
NATO regards the blasts as sabotage and has since "enhanced patrols near critical undersea infrastructure."
Some media outlets have claimed that Russia may be preparing to repair and launch the Nord Stream 2 gas pipeline.
Friday is day 660 of Russia's war on Ukraine.
Russia invaded Ukraine on February 24, 2022, launching the largest military campaign in Europe since World War II.
(pm/gs)
Source: biznesalert.pl, energetyka24.pl
