Image caption The think tank has questioned how a Scotland-only army would cope

An independent Scotland would have a limited defence force which would struggle to recruit and retain personnel, a report has suggested.

Think tank The Scotland Institute has produced what it claimed was a "comprehensive review".

SNP defence spokesman Angus Robertson said independence would protect defence jobs and stop "Whitehall making bad decisions on our behalf".

Voters in Scotland are going to be asked to decide on independence.

On 18 September next year, the electorate will say "yes" or "no" to the question: "Should Scotland be an independent country?"

I cannot see how slicing up a competent and well established military will aid either the United Kingdom or an independent Scotland Major-General Andrew Mackay, Defence report chairman

Think tanks, experts and lobbyists, as well as the UK and Scottish governments, have been producing their own reports on the impact of independence.

This latest one, titled Defence and Security in an Independent Scotland, had input from armed forces personnel, defence academics, former secretaries of defence and senior officials from Nato, UK MOD and the EU.

It was chaired by Major-General Andrew Mackay who commanded a Task Force in Afghanistan and served in the army for 27 years.

In the report's foreword, he said: "I cannot see how slicing up a competent and well established military will aid either the United Kingdom or an independent Scotland.

"Indeed, I see very real risks to the people of Scotland, be it from the loss of jobs and the local economic impact that the inevitable removal of the Faslane naval base would bring, the huge costs necessary to start building the armed forces from afresh, the loss of access to sensitive intelligence materials and the inevitable dilution in the quality and number of the armed forces of this small island, which to date have had such a profound effect upon the course of world events."

The report suggested that after independence Scotland would be more vulnerable to terrorist and cyber attack because it would need time to establish an intelligence body capable of dealing with these threats.

Limited functions

It insisted that post-Yes Scotland would not be either "cheaper or easier to defend".

To have serious credibility, this report must also outline Scotland's vast defence assets, as an independent Scotland would of course not be starting from scratch Angus Robertson, SNP defence spokesman

The authors believed what would result would be a "very small military force, able to perform a limited number of niche functions such as protecting Scotland's fisheries and oil refineries".

It also judged that an independent Scotland would find it difficult to maintain an air force "of any consequence" and would possess a "truncated navy stripped of submarine forces".

However, Nationalist MP Mr Robertson hit back saying that there would be better defence decisions in Scotland post independence.

He was critical of the UK government's move in recent years to close bases, disband units and scrap "vital" capabilities like maritime patrol.

Mr Robertson added: "To have serious credibility, this report must also outline Scotland's vast defence assets, as an independent Scotland would of course not be starting from scratch - but the key difference is that after independence, Scotland would decide how to spend all of the money it contributes to defence.

"A sovereign Scotland can therefore increase spending on conventional defence in Scotland while making savings from Trident. An annual defence and security budget of £2.5bn would be around £500m more than is currently spent by the UK government in Scotland - but £1bn less than Scots taxpayers currently contribute to the UK's defence policy.

"Normal democratic countries make their own defence decisions - our best future is to make the right decisions for Scotland and we will be able to do that with independence."