The Russian army accused Ukraine of a "massive" drone attack on its Black Sea Fleet in Crimea on Saturday, claiming the UK helped in the strike that damaged a vessel.
Sevastopol in Moscow-annexed Crimea, which has been targeted several times in recent months, serves as the headquarters for the fleet and is a logistical hub for operations in Ukraine.
The Russian army claimed to have "destroyed" nine aerial drones and seven maritime ones, in the Saturday morning attack on the port.
Moscow's forces alleged British "specialists", whom they said were based in the southern Ukrainian city of Ochakiv, had helped prepare and train Kyiv to carry out the strike.
In a further singling out of the UK -- which Moscow sees as one of the most unfriendly Western countries -- Moscow said the same British unit was involved in the explosions which damlaged the Nord Stream gas pipeline last month.
Moscow's military said ships targeted at their Crimean base were involved in a UN-brokered deal to allow the export of Ukrainian grain.
The UK defence ministry on Saturday rejected claims by Russia that its specialists were involved in either series of attacks.
The defence ministry tweeted: "To detract from their disastrous handling of the illegal invasion of Ukraine, the Russian Ministry of Defence is resorting to peddling false claims on an epic scale."
Crimea a crucible of conflict
Attacks on Crimea, annexed by Moscow in 2014, have increased in recent weeks, as Kyiv presses forward with a counter-offensive in the south to retake territory held by Moscow for months.
Moscow-installed authorities in Kherson, just north of Crimea, have vowed to turn the city into a fortress, preparing for an inevitable assault.
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