Russia said its forces fired warning shots at a British destroyer off the coast of Crimea on Wednesday, but the UK has denied the claims.
The Russian defence ministry said the HMS Defender made a 3km incursion into Black Sea waters that Russia claims near the peninsula, which it annexed from Ukraine in 2014.
The UK’s Ministry of Defence denied that any shots were fired directly at the vessel.
Ben Wallace, UK defence secretary, said HMS Defender carried out a “routine transit” on Wednesday morning from Odessa towards Georgia across the Black Sea.
“As is normal for this route, [the destroyer] entered an internationally recognised traffic separation corridor. She exited that corridor safely at 0945 BST. As is routine, Russian vessels shadowed her passage and she was made aware of training exercises in her wider vicinity,” Wallace said.
The Russian defence ministry said that, after HMS Defender did not respond to a threat from Russian forces to open fire, a coastguard ship fired warning shots at it.
Minutes later, Russia’s Black Sea Fleet scrambled a Su-24M attack aircraft that dropped four high-explosive fragmentation bombs in the ship’s path before it exited the waters, according to the ministry.
The disputed claims come at a time of heightened tensions between Russia and the Nato alliance. Most countries do not recognise Russia’s control of Crimea and the surrounding waters.
Nato countries have sent several warships on visits to the area in recent years in shows of support to Ukraine, prompting criticism from Moscow.
In 2018, Russia seized three Ukrainian navy vessels attempting to pass the peninsula to Kyiv-controlled territory via the Kerch Strait.
HMS Defender, which forms part of the UK’s carrier strike group deployment, is in the Black Sea this week as part of an exercise to enforce Ukraine’s territorial integrity.
The head of the Royal Navy met Ukraine’s deputy minister of defence on board the destroyer in Odessa on Tuesday to sign an agreement related to Britain helping to boost Ukraine’s naval capabilities.
The co-operation will include training of Ukrainian navy personnel, creation of new naval bases, and the purchase of two Sandown class minehunters.
Ukrainian special forces were performing joint exercises practising “the unexpected seizure of enemy ships” on HMS Defender with their US and UK counterparts, Kyiv’s defence ministry said in a statement.
Dmytro Kuleba, Ukraine’s foreign minister, wrote on Twitter in response to Moscow’s claims that “Russia’s aggressive and provocative actions in the Black and Azov seas, its occupation & militarisation of Crimea pose a lasting threat to Ukraine and allies”.