Scottish independence: UK government highlights 'benefits' of border protection
The UK government has said that Scotland benefits from border protection and international influence as part of the Union.
Its latest paper in the Scottish independence debate focuses on borders and citizenship.
The document argues that visa services and trade promotion benefits "every UK citizen".
The Scottish government has claimed an independent Scotland "will not require the same scale of diplomatic services".
The paper is the 10th produced by the UK government and the second since the Scottish government published its own White Paper on independence last November.
Launching the paper, the UK government's Scotland Office said: "More than 20,000 staff in different agencies with resources of more than £2bn are managing the UK border for the direct benefit of every UK citizen regardless of where they live or work."
The UK government said that in 2011-12 it had:
•Granted 2.23 million visas from 2.65 million applications.
•Processed 21,875 asylum claims.
•Patrolled over 63,000 miles of territorial waters and searched more than 2,000 vessels (2010-11 figures).
•Prevented over four and a half tonnes of Class A drugs from entering the country.
•Intercepted 455 million smuggled cigarettes, protecting tax revenue of over £166 million.
•Facilitated international trade worth about £573bn and collected over £34bn from customs and excise duties and import VAT (2011 figures).
'Secure and trusted'
The paper said: "In 2012, 3.6 million Scottish residents went overseas. The holders of UK passports - one of the most secure and trusted in the world - enjoy visa free travel to 173 other countries and can access consular support in over 170 countries."
The Scottish government has said it would bring in a separate Scottish passport under independence, but says Scots would be free either to retain their British passport or hold both.
Its White Paper on independence says: "There are inherent advantages in being a smaller, well-governed, independent state in a rapidly-changing world, with the ability to respond to developments and with the scale to bring national institutions and civic society together quickly if need be.
"By focusing our diplomatic efforts together flexibly on key national priorities, Scotland will not require the same scale of diplomatic service as the UK currently maintains."
The UK government's paper also argues that Scots benefit from free movement around the UK, including the nearly one million who are resident in England, Wales and Northern Ireland.
Deputy First Minister Nicola Sturgeon has sent an open letter to Scottish Secretary Alistair Carmichael responding to the paper.
Ms Sturgeon said: "This latest paper from the Project Fear library lacks all credibility. Firstly, it ignores the 22% staff cuts that the UK government is making to the UK Border Agency and the Scottish government's own proposal to establish a Scottish Border and Migration Service.
"And secondly, it completely ignores the reality of the Common Travel Area, in which the UK and Ireland already have no border controls but differing immigration policies.
"Thankfully, people in the rest of the UK are far more reasonable than Mr Carmichael and his colleagues, with polls showing that the vast majority would expect their government to work with an independent Scotland to ensure continued co-operation within the Common Travel Area."