An independent Scotland could face "complex and long negotiations" before it could become a member of the European Union, the UK Government will warn today
The Westminster coalition will also say that it could "not be assumed" that if Scotland became independent it would be able to negotiate the same "favourable terms of EU membership which the UK enjoys".
Foreign Secretary William Hague and Chief Secretary to the Treasury Danny Alexander will be in Glasgow today to launch the latest in a series of papers looking at the impact of Scottish independence.
The latest of these Scotland Analysis papers will focus on European Union (EU) and international issues.
Ahead of its publication, Scottish Deputy First Minister Nicola Sturgeon called on Mr Hague to confirm the Conservative Party's planned referendum on EU membership means that "an exit from the EU is a possible consequence of Scotland continuing to be governed by Westminster".
Ms Sturgeon said: " We have set out a clear and common-sense approach to Europe in which Scotland will be an active and productive member of the European Union. That is overwhelmingly in Scotland's best interests."
She told the Foreign Secretary: "It is clear that the agenda on Europe within your Government and at Westminster as a whole is being driven by a fear of UKIP which does not exist in Scotland.
"Any discussion of Europe and foreign affairs by your Government must acknowledge the impact of the in/out referendum on membership of the European Union that your Government proposes.
"It seems to me that your paper - to have a shred of credibility - must make explicitly clear that very real risk to Scotland of remaining in the Union."
The UK Government paper, however, will warn the outcome of negotiations on an independent Scotland's membership of the EU could "prove less advantageous than the status quo".
The paper will state that all new EU member are required to commit to joining both the euro and the Schengen common travel area, in which people can travel between countries without showing passports.
The Scottish Government hopes to retain the UK's opt-outs for these, but the paper will say this is "not in the Scottish Government's gift" and that Holyrood ministers would " have to convince all 28 EU member states".
Meanwhile, the SNP administration's plan to continue charging students from the rest of the UK to study at universities north of the border is likely to "face challenges on the grounds that is is contrary to EU law", the UK Government will warn.
Current EU rules prohibit states from discriminating on the grounds of nationality, meaning Scotland has to give fee-free university education to EU students from outside the UK in order to keep studying at university free for Scottish students.
But it can impose tuition fees on students from England, Wales and Northern Ireland because the EU does regulate for discrimination within member states.
The Scottish Government's white paper on independence proposes to continue to charge students from England, Wales and Northern Ireland if Scotland votes to leave the UK in September's referendum.
The white paper argues that the ''unique and exceptional circumstances'' an independent Scotland would face as a result of factors such as the ''relative size of the rest of the UK'' and the policy of university tuition fees south of the border would allow the Scottish Government to ''justify objectively the continuation of our current policy'' in a way which is ''compatible with EU requirements''.
But the UK Government paper will state: "Should the government of an independent Scottish state pursue this policy, it is likely that it would face challenges on grounds that it is contrary to EU law.
"Contrary to claims made by the Scottish Government, it is likely that the existing policy on tuition fees would have to be overturned, either to impose tuition fees for Scottish and EU students or to remove the fee system for students from other parts of the UK. This would have a substantial impact on funding streams for Scottish universities."
Ms Sturgeon has already argued an objective justification can be made for the fees policy ''because of the particular circumstances of the geography of Scotland and the rest of the UK, and the policy that exists in other parts of the UK''.
Mr Hague yesterday highlighted the shared values between Scotland and the rest of the UK and said that maintaining the Union would give the UK greater international ''clout'', meaning it would be ''better able to make a difference in the world''.
He also stressed the business and trade benefits of the UK staying together, the reassurance provided to Scottish people overseas by the Foreign Office's consular services, the UK's level of aid donation and the benefits of having a greater voice on the world stage.
The Foreign Secretary said: ''The United Kingdom is one of the most successful political and economic unions there has ever been. We can act as a powerful force for good in the world, but our strength lies in our unity. We are stronger and safer together."