An independent Scotland would have to renegotiate its relationship with world bodies while the rest of the UK would continue as before, according to two experts in international law.
Professors James Crawford and Alan Boyle set out their opinions, ranging from the European Union to Interpol, as part of an analysis paper due to be published by the British Government.
It follows work across Whitehall departments to try to explain how Scotland and the rest of the UK "benefit" from political union.
The Scottish Government was first off the mark last week with a short "road map" paper, suggesting that negotiations between Scottish ministers and the UK Government, EU and international organisations could be concluded by March 2016, assuming a Yes vote in autumn 2014.
Prime Minister David Cameron, speaking before the launch in Edinburgh, said: "I know those arguing for independence are already preparing their separation transition plan, as though they've got this in the bag, but to me that is wrong.
"It's like fast-forwarding to the closing credits before you've been allowed to see the movie.
"The Scottish people still have many months to think about this decision and they are hungry for facts, evidence and expert opinion to help them make up their minds."
While Monday's publication features expert legal opinion, it does not include specific advice from the European Commission on the implications of Scottish independence in the EU.
A summary, issued in advance from Downing Street, said the UK Government is taking the "unusual step" of publishing full legal opinion from experts. The 57-page opinion finds that the "overwhelming weight" on precedent suggest Scotland will become a new sate while the remainder of the UK will continue.
"This means that if Scotland became independent, only the remainder of the UK would automatically continue to exercise the same rights, obligations and powers under international law as the UK currently does, and would not have to re-negotiate existing treaties or re-apply for membership of international organisations," the summary states.