The incident on Tuesday involved a Russian frigate, the Admiral Grigorovich/MINISTRY OF DEFENSE
A Russian warship fired warning shots near a UK-registered yacht in the English Channel on Tuesday morning after the two vessels came into close contact.
The incident, involving Russian frigate the Admiral Grigorovich, happened between the Isle of Wight and Normandy shortly before midday.
BBC News understands that the small, motor-less yacht had drifted towards the warship in foggy conditions after setting off from the UK.
The Russian Defence Ministry said the yacht had been on a "dangerous approach" towards the warship, and its crew fired into its path with rifles after making several attempts to contact it over the radio and after launching warning flares.
It also said its sailors had acted in "strict accordance with international shipping regulations", while the British Ministry of Defence said it was investigating the incident.
A UK government source told BBC News a couple in their 60s were onboard the yacht at the time. They said they did not hear when the Russian frigate sounded its horn. No injuries or damage have been reported.
It comes days after Royal Marine Commandos intercepted a Russian shadow fleet tanker carrying sanctioned oil in the Channel on Sunday, in the first operation of its kind carried out by the British military.
However, it is understood British officials do not view the incident as being linked to Sunday's operation.
Russian warships regularly pass through the Channel in international waters and are routinely monitored by Royal Navy vessels.
The frigate thought to be involved in Tuesday's incident was being shadowed by the HMS Mersey, it is understood.
On Monday, the Navy said the Admiral Grigorovich was being tracked by the HMS Tyne and HMS Mersey over the weekend, in what it described as a "routine operation" after it was spotted off the coast of Brest in France.
On Tuesday morning, British authorities received reports from the yacht's occupants that the Russian vessel had fired warning shots from around 500 yards (457 meters) away - a relatively near distance by the standards of sea travel.
The incident happened around 20 nautical miles - around 23 standard miles - south of the Isle of Wight, outside UK territorial waters.
Last week, a Nato source told BBC Verify that the Admiral Grigorovich had been ordered by Moscow to escort shadow fleet vessels through the Channel.
The frigate is understood to have been operating in the area for some time and had been repeatedly re-supplied by a repair vessel.
Satellite images reviewed by BBC Verify have shown the repair vessel, the PM-82, operating between the Channel and the North Sea in recent months.
Nato officials believe the PM-82 delivered food, water and other supplies to the Admiral Grigorovich, allowing it to stay at sea for extended periods of time and lead Russian convoys though the Channel.
In April, the frigate was reported to have escorted six shadow fleet vessels through the waterway while being monitored by the Royal Navy.
While Tuesday's incident has been viewed as an isolated incident so far by the MoD, it comes at a time of heightened tension with Russia over the UK's ongoing support for Ukraine.
