A report by a leading thinktank says that Britain's nuclear missiles could be moved to the South West if Scotland votes for independence – and their warheads stored in the Fal Estuary.
The report, compiled by the Royal United Services Institute (Rusi), says the location, just between Falmouth and Truro, is the option "given most credence to date" and would provide "good shelter and a comparatively isolated location," to store the warheads.
It says Devonport in Plymouth would be the obvious choice as the new home for Britain's nuclear submarine fleet, although acknowledges there would be safety concerns.
"Introducing nuclear-armed [submarines] to Devonport will unavoidably introduce a new risk that an accidental ignition of one or all of a submarine's Trident D5 missiles could spread radioactive material over some of Plymouth's 260,000 inhabitants," it says.
The Trident nuclear weapons system is currently based at a submarine base in Faslane 40km west of Glasgow, with a further nuclear warhead depot at nearby Coulport.
The report says any relocation would not take place before 2020 – the target date set by the current Scottish government – and could be put off until 2028 when a new fleet of Trident submarines enters service.
It goes on to say that local opposition would be inevitable, but notes that the Ministry of Defence is reported to have waived safety requirements at Coulport in the 1970s in similar circumstances.
"The secretary of state has the power to restrict the examination of plans to only those with suitable clearance in a case that 'may involve the interests of national security'," it says.
"Furthermore, if a planning application is likely to be refused, any urgent development 'of national importance' can be submitted directly to the secretary of state for communities and local government for planning approval."
