Roderich Kiesewetter, a German opposition politician, said it was likely that a Russian intelligence agent was simply able to join the call, which Luftwaffe officers connected to on their mobile phones.

One participant on the call mentions that he could send further information via WhatsApp, in a further possible security breach.

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German Chancellor Olaf Scholz described the leak as “very serious” and ordered an investigation.

It comes after he suggested last week that British troops were in Ukraine helping to fire Storm Shadow missiles. French President Emmanuel Macron had earlier faced a backlash from NATO allies for suggesting troops could be sent to Ukraine in a limited capacity.

The call also further damages the chances of Germany sending Taurus missiles to Ukraine. Scholz has so far blocked the move over fears they could be used to strike Moscow.

In the call, officers also discussed whether Taurus cruise missiles could possibly strike the Kerch Bridge between the Russian mainland and the occupied Crimea peninsula.

This was described by former Russian president Dmitry Medvedev as proof that Germany is “preparing for war against Russia”.

The discussion between Gerhartz and several other senior officers was confirmed by the German Defence Ministry to be authentic.

A spokesperson told German tabloid Bild that “there are indications that an insufficiently secure means of communication was used in view of the content that was obviously discussed. This is, among other things, the subject of further investigations”.

Bob Seely, a British Conservative MP, called Germany “incredibly complacent”, while Alec Shelbrooke, a former defence minister, described the leak as an “amateur blunder”.

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The intercepted call marks one of Germany’s worst security breaches since the Cold War.

“The question arises as to whether this is a one-off incident or a structural safety problem,” Konstantin von Notz, a member of the Greens, told German broadcaster RND.

The interception comes as Russia has made a series of battlefield gains, reversing much of Ukraine’s counter-offensive last northern summer.

Kyiv is pleading for more weapons and funding, much of which is blocked by allies of Donald Trump in the US Congress in a row over migration and the Mexico border.

The Telegraph, London

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