Russia has deployed a warship armed with cruise and hypersonic missiles close to a German island in the Baltic Sea.

The Admiral Kasatonov, a frigate equipped with nuclear-capable Zircon hypersonic missiles, was seen last week off the coast of the island of Fehmarn, a popular destination for tourists, following Kremlin threats to attack British and EU vessels.

Constructed in 2020, Admiral Kasatonov is said to be one of the most advanced warships in the Russian navy. It is capable of long-range strikes as well as anti-submarine warfare.

The appearance of the warship in the Baltic, a vital shipping zone, appears to mark the latest escalation between Russia and Nato.

On Sunday, The Telegraph revealed that Russia was building secret bases near its border with Ukraine. They are being used to build hi-tech attack drones capable of striking deep inside Nato territory, posing a long-term threat to the alliance.

A recent US intelligence report has warned that Russia could launch an attack on the Western alliance to test its resolve within weeks. This could take the form of a small-scale attack on Poland or a Baltic state, as The Telegraph revealed earlier this month.

In recent months, Britain and France have seized commercial vessels suspected of transporting oil and other goods on behalf of Russia, in violation of international sanctions.

The secretive network of ageing Russia-linked ships, which are in poor condition and generally sail under obscure foreign flags, has been called the Russian shadow fleet.

Admiral Kasatonov is the second Russian warship to be seen in the Baltic in recent weeks, following the deployment of the destroyer Admiral Levchenko in late July.

The Telegraph approached the German military for comment about the warships but did not receive an immediate response. Moscow has not commented on the deployments.

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