The Yantar was warned off in November after a Royal Navy submarine surfaced close to it and told the crew that it had been secretly tracking its movements.
The Yantar then sailed for the Mediterranean but returned this week as it sailed through the English Channel, flanked by the HMS Somerset and HMS Tyne.
The navy says the ship was monitored by NATO in waters close to France before they took over, launching a helicopter to locate it.
UK Defence Secretary John Healey says he has a clear message for Russian President Vladimir Putin.
“We know what you are doing, and we will not shy away from robust action to protect Britain,” he says.
“Alongside our Joint Expeditionary Force and NATO allies, we are strengthening our response to ensure that Russian ships and aircraft cannot operate in secrecy near UK or NATO territory.”
He also vowed that the UK would keep cracking down on Russia’s shadow oil fleet and prevent funding of his invasion of Ukraine.
MONITORING
The UK Defence Ministry says the Royal Air Force will add a twin-jet P-8 maritime patrol aircraft to a new NATO force, codenamed Baltic Sentry, which is protecting offshore infrastructure in the Baltic Sea.
The UK is also using a new AI tracking system, Nordic Warden, to monitor the Russian shadow fleet.
Last year, the UK sanctioned 93 oil tankers which Putin has been using to soften the blow of international sanctions and bankroll his illegal war in the Ukraine.
The Royal Fleet Auxiliary, which supports Royal Navy operations, is a key element of the UK’s strategy to safeguard offshore infrastructure.
The Navy’s multi-role ocean surveillance ship, the RFA Proteus, can deploy submersible drones to assess undersea cables and pipelines.
The Proteus was also involved in shadowing the Yantar last year.
