Germany has admitted the apparent hack by Russia of a military meeting where officers discussed giving Ukraine long-range missiles - and possible targets.

Audio of the video-conference meeting was posted to social media by the head of Russia's state-run RT channel.

The officers discuss how the missiles could hit the Kerch Bridge, which links Russia to the illegally annexed Crimea.

Russian politicians said the audio proved that its "sworn enemy" was planning attacks.

Germany's chancellor Olaf Scholz on Saturday called the apparent leak "a very serious matter and that is why it is now being investigated very carefully, very intensively and very quickly".

According to Der Spiegel magazine, the videoconference was not held on a secret internal army network but on the WebEx platform.

The 38-minutes of audio was posted by RT chief Margarita Simonyan on Friday, who said it was proof Germany was planning strikes on Crimea.

In the recording, discussions can be heard on the possible use by Ukrainian forces of German-made Taurus missiles and their potential impact.

A spokeswoman for the German defence ministry told the AFP news agency that a secret air force conversation had been tapped.

However, she said that she was "unable to say for certain" whether the voices on the recording had been tampered with before publication.

Russian foreign ministry spokeswoman Maria Zakharova demanded that Germany "promptly" provide explanations.

"Attempts to avoid answering the questions will be regarded as an admission of guilt," she said.

Dmitry Medvedev, the deputy head of Russia's Security Council, said on Telegram: "Our age-old rivals - the Germans - have again turned into our sworn enemies."

"Look, with what thoroughness and in such detail the (Germans) discuss striking our territory with long-range missiles, choose targets to hit and discuss how to inflict the maximum harm to our motherland and our people," he said.

Russia's Foreign Minister Sergei Lavrov said on Saturday that the discussion betrayed the "cunning plans" of the German armed forces, which he said had committed "a blatant self-exposure".

Kyiv wants Germany to provide it with Taurus missiles, which have a range of around 500km (300 miles).

Mr Scholz has so far refused, fearing it would lead to an escalation of the conflict.

France and Britain have supplied Kyiv with Scalp or Storm Shadow missiles, both of which have half the range.

Roderich Kiesewetter, from Germany's opposition conservatives, warned that further recordings may also be leaked.

"A number of other conversations will certainly have been intercepted and may be leaked at a later date for Russia's benefit," he told broadcaster ZDF.

It can be assumed "that the conversation was deliberately leaked by Russia at this point in time with a specific intention", namely "to prevent Taurus delivery by Germany", he said.