Late last month, it was reported that British forces had put in place contingency plans to board and seize Russian ships off the UK coast if there is evidence they are damaging undersea pipelines.

Moscow has responded to the suggestion – saying it would be forced to take action.

“If this were to hypothetically happen, it would be a violation of the [UN] convention [on the law of the sea],” ambassador to the UK Andrey Kelin said in an interview with the Rossiya-24 television channel.

“Naturally, we have the right to defend our interests by legal means. But it is unlikely to come to that, as our response will be inevitable, fully lawful, and justified.”

The Russian diplomat described the statements on the potential detention of Russian ships implied “some readiness of the British Navy, a tiny one now, to some sort of concrete actions”.

“But, obviously, this will require a political decision,” he added.

UK Defence Secretary John Healy said last month he had ordered the Royal Navy to intercept Russia’s Yantar spy ship in the English Channel in November.