While the Royal Air Force has been regularly scrambled to intercept Russian military aircraft nearing British airspace, a parallel effort by President Vladimir Putin’s naval forces to probe the defences of the UK and its Nato allies across a large swathe of the Atlantic has been kept out of the public eye.
The stretch of ocean between Greenland, Iceland and UK – known as the GIUK gap – was a key Cold War hotspot as Soviet submarines en route to operations in the Atlantic sought to evade British and Nato surveillance.
Moscow’s desire to re-establish itself a major military power amid worsening relations with the West has seen a fresh rise in incidents involving submarines around the GIUK gap.
The Ministry of Defence does not make public any statistics relating to foreign incursions in UK territorial waters, defined as the area stretching 12 miles from the coast.
The MoD rejected an FOI request from The Scotsman’s sister title the i, requesting details of such incidents on the grounds of national security.
But figures collated from information in the public domain, including media reports, shows there has been a sharp increase in the number of known naval approaches or encroachments into UK waters. Of ten incidents between 2005 and 2015, eight occurred in the last three years.
A further encounter happened in October this year when up to three Russian submarines sailing with a convoy headed for Syria were tracked by a Royal Navy submarine as they passed through the Irish Sea.
Experts have warned that the incursions fit a pattern of Russia testing the defences of Britain and other Nato countries as well as seeking potentially crucial information about the UK’s nuclear deterrent based in Faslane, Scotland.
On at least two occasions in the last 12 months, the Royal Navy has been scrambled off the Scottish coast to investigate suspicions that a Russian submarine was tracking one of Britain’s Vanguard-class boats carrying Trident missile in an attempt to obtain an “acoustic fingerprint” to allow the vessels to be tracked.
Dr Andrew Foxall, director of the Russia Studies Centre at the Henry Jackson Society, a London-based think-tank, said: “Through its intrusions, Russia has been able to gain valuable information about the chain of command, and preparedness of elements within the UK defence system.
“Russia’s submarines, which lurk off naval bases in Scotland, seek even more sensitive information – the ‘acoustic signature’ made by the Vanguard submarines.
“If Russia were able to obtain a recording of the ‘signature’, it would have serious implications for the UK’s nuclear deterrent – Russia would be able to track Vanguards and potentially sink them before they could launch their missiles.”
The intensification of Russian interest in Britain and the GIUK gap has raised concerns about the UK’s ability to monitor and contain any threat it may pose.
On both occasions when Moscow’s submarines were suspected of operating off Faslane, Britain had to seek assistance from allies – namely Canada, France and the United States – in its efforts to track the intruder.
The decision to scrap the RAF’s entire fleet of Nimrod surveillance aircraft has, in the words of one figure with knowledge of the UK’s defence capabilities, “left us with our pants down”. The Ministry of Defence this summer placed an order for nine state-of-the-art American surveillance jets – the Boeing P-8 Poseidon – to replace the Nimrods but the first delivery is not due until 2019 at the earliest.
Magnus Nordenman, director of the Transatlantic Security Initiative at the Washington-based Atlantic Council think tank, told i that Britain and Nato had the ability to track Russian submarines but cuts had left then unable to do so constantly.
He said: “The alliance cannot currently afford to do that on a consistent basis, due to the fact that naval units have been some of the hardest hit during the period of defence austerity.” Dr Foxall added:
“There is a fear or concern among Nato members of what might happen if they over-react to this Russian activity.
“There is a fear of getting into a confrontation.
“But as Russia has become increasingly aggressive in its foreign policy, there is a growing realisation that there needs to be a more robust response.
“An awful lot of Nato members over the last decade have got rid of or downsized capabilities in the belief that conventional warfare was a thing of the past. Now they are once more having to take that threat seriously.”
The MoD did not respond to a request to comment.