The debate over the place an independent Scotland would occupy in the European Union will receive a dramatic intervention from Foreign Secretary William Hague in Glasgow.
Hague will deliver the findings of a report called Scotland Analysis: EU and International, in which the government presents an analysis of Scotland's putative entry into the EU, following a yes vote in September's referendum.
Speaking on the Radio 4's Today Programme, Hague rebuked the claim by First Minister Alex Salmond that the entry of an independent Scotland into the EU was a foregone conclusion.
"The Scottish government has talked about a seamless membership but that is not how it is when you look at the facts.
"Alex Salmond can say what he wants but it would be a very difficult negotiation. Scots would be paying more to get less from the European Union. There is no doubt about that."
Hague will list a number of reasons why Scotland should remain within the union and how it gets a better deal on the EU through being part of the UK.
"Together, as the world's sixth largest economy, we have a voice that is heard in every major international forum – from the UN Security Council to the G20 to the European Union.
"Together, we are the world's number one soft power, with the British Council in 110 countries promoting universities such as St Andrews and Edinburgh that rank among the world's finest, and helping to bring 40,000 students a year to Scotland."
Scottish families also benefit from the consular services offered by the Foreign Office and Scottish businesses benefit from UK Trade and Investment, Hague will add in his speech.
But the sort of arguments being put forward by Hague about Scotland getting a good deal on EU membership via the UK have been rebutted on a number of occasions from different members of the Scottish government.
Richard Lochhead, the Scottish government's cabinet secretary for rural affairs and the environment, has repeatedly said that Scotland's farmers do not get a fair deal from the British government on the common agricultural policy.
"If Scotland had been independent during the most recent EU farming talks we would have qualified for an extra €1bn of funding - Scotland's billion euro boost," he said.