ARMED forces in an independent Scotland would "most likely" be short of personnel, a retired Air Marshal has told MPs.

But the appearance of Iain McNicoll and his colleague, retired Rear Admiral Martin Alabaster, before the Commons Defence Committee was hailed by the SNP as slaying a number of "Unionist myths" on defence, from Nato membership to shipbuilding.

Both were asked detailed questions by MPs about the defence implications of possible Scottish independence and both suggested it was difficult to be specific because the SNP's foreign and security policy was not yet fully formulated.

Mr McNicoll said the size and scale of an independent Scottish defence forced hinged on something he had "not yet seen beyond broad assertions and sweeping generalities, which is a proper foreign and security policy translated into defence needs identified and working out how these can be met".

He accepted a similar-sized Denmark was a "reasonable comparator" with an independent Scotland with a comparable budget for a defence force but asked: "What do you need it for?"

On Nato he said: "There are other members of Nato who do not accept nuclear weapons. It's possible, in theory, for Scotland not to accept nuclear weapons."

Last night, Angus Robertson for the SNP, praised the "refreshingly sober views" of the former military top brass.