- By Jessica Parker and Laura Gozzi
- BBC News in Berlin and London
German Defense Minister Boris Pistorius said allies' trust in Germany was “not broken”.
Defense Minister Boris Pistorius has said a meeting of senior German air force officers was leaked through a “personal error” by Russian sources.
He said the investigation ruled out that a Russian spy participated in the call undetected.
Mr Pistorius said the call was leaked because a participant dialed through an unsecured line.
This allowed Russia to intercept the dialogue, he said.
In the recording, four senior German military officers appear to have discussed the possibility of Ukraine using German-made Taurus cruise missiles to attack the Kerch Bridge linking Russia with the Crimean peninsula, which was illegally annexed from Ukraine in 2014.
German Chancellor Olaf Scholz has repeatedly ruled out sending Taurus missiles to Ukraine.
Mr Pistorius said the call took place on a more secure version of the Webex conference site hosted on German military servers.
Russia's state-run RT channel released an audio recording of the meeting last week.
Speaking at a press conference on Tuesday, he said a participant had dialed into the meeting through an “unauthorized connection”, leading to the leak.
Mr Pistorius confirmed a disciplinary inquiry was underway but suggested he did not want to see heads roll.
“At present, personal consequences are not on the agenda. I will not sacrifice my best officers for that. [Russian President Vladimir] Putin's games,” he said.
The unsecured line was used by an officer dialing from Singapore, where the military air show was held at the end of February.
The breach caused great concern about Germany's security among allies including France and the UK.
But Mr Pistorius denied the Allies' trust in Germany had been broken.
“Everyone knows the danger of such interference, and everyone knows there is no such thing as absolute security,” he said.
The Kremlin framed the recording as evidence of direct Western involvement in the conflict in Ukraine.
Spokesman Dmitry Peskov said on Monday that the leaked conversation “discusses Bundeswehr substantially and specifically plans to attack the Russian border”.
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