British jurists: independent Scotland would lose EU status

It adds that Scotland would have to apply to join other multinational bodies, such as the International Monetary Fund, Nato and the UN, with no guarantee of a place.

The paper, based on an analysis by law professors James Crawford from Cambridge University and Alan Boyle from the University of Edinburgh, comes ahead of a Scottish referendum on independence next year.

It is set to make interesting reading in Catalonia, which aims to hold a vote also in 2014 on splitting from Spain.

Crawford and Boyle warn that: "There is no clear precedent for a metropolitan part of an EU member state becoming independent and then either claiming automatic membership or seeking in its own right to join the EU … This means that the following discussion must necessarily be somewhat speculative."

But they add: "On the face of the EU treaties and other indications, it seems likely that Scotland would be required to join the EU as a new member state."

They note "this is not to suggest that it is inconceivable for Scotland automatically to be an EU member … [but] it is not required as a matter of international law, nor, at least on its face, by the EU legal order."

They also say that even if Scotland kept EU law on its books "it would not cause Scotland or its citizens to have any rights or obligations under the EU treaties."

"There is no rule that, for example, it would somehow automatically be entitled to the UK's opt-outs from the euro or justice and home affairs. The terms of accession would have to be agreed with other member states."

British officials in their accompanying analysis added that Scotland would not just lose EU membership, but also its very statehood, if it split.

"In the eyes of the world and in law, Scotland would become an entirely new state … Scotland would be required to apply to and/or negotiate to become a member of whichever international organisations it wished to join," they said.

They noted that it would have to redraft "thousands of international treaties and agreements to which the UK is currently party and which would default to the continuing UK."

They also raised the spectre of border controls for the first time in centuries on the British mainland.

"As the UK has no intention of joining the Schengen area, this would involve border controls between Scotland and the continuing UK," they said.

For her part, Nicola Sturgeon, the deputy leader of the pro-independence Scottish National Party, gave an early counter-blast on BBC radio the same day.

"These are matters that will be settled not by law but by negotiation and agreement," she said.

She indicated that the tone of the British analysis suggests London would try to use its power in the EU to stop Scotland from getting in on good terms.

"If the UK government is really saying that they would, in the event of a Yes vote [on Scottish secession], go out of their way to make life difficult for Scotland, not only is that very arrogant but it would also put them in a position of arguing against their own interest," she added.