LONDON : This week’s Scottish referendum is a lot about the economy, experts say, as voters mull the outlook for their currency, oil revenues, jobs, national debt and EU membership. Scots will cast their ballot Thursday in a knife-edge vote that could see Scotland scrap its historic union with the rest of UK. Cameron, who wants Scots to stay in the union, has already vowed that he will not allow an independent Scotland to keep using the pound, and ruled out any form of currency union. Other key issues are how an independent Scotland will manage to pay its share of the UK’s national debt, and how it will raise the extra billions needed to fund a credible “lender of last resort” to any stricken banks.

Scottish National Party (SNP) leader and First Minister Alex Salmond, who heads Scotland’s devolved government, argues independence will allow it to take full control of economic policy — how taxes are raised and spent.

Divisions have also emerged over the potential of oil reserves in the North Sea off the coast of Scotland — which has a direct impact on revenues.

The Scottish government is predicting up to £38.7 billion ($62.9 billion, 48.5 billion euros) in revenue over the next five years, while Britain is forecasting £17.6 billion.

- Questions over economy -

“The ‘Yes’ campaign faces many questions over the economy, not least the issue around what currency it takes and how it intends to pay its share of the national debt, but also concerns around the overstating of North Sea oil reserves and their likely tax receipts,” said Nick Lewis, head of trading at Capital Spreads.

The pro-unity camp also argues that the 300-year-old union has allowed Scotland to capitalise on its strengths in the global market, adding that independence would endanger an estimated 270,000 Scottish jobs that are directly linked to trade with the rest of the UK.

Economic concerns have intensified after a string of major financial firms — Royal Bank of Scotland, Standard Life, TSB, Lloyds Banking Group and Clydesdale Bank — warned they could move their registered offices to England in the event of a “Yes” vote.

Bank of England governor Mark Carney has warned that a currency union is “incompatible” with sovereignty, adding that an independent Scotland would need to raise billions more pounds of extra reserves to fund a lender of last resort, or central bank, to ensure financial stability.

Nobel laureate economist Paul Krugman warned Scotland against using the pound without a currency union.

“Everything that has happened in Europe since 2009 or so has demonstrated that sharing a currency without sharing a government is very dangerous,” Krugman said in the New York Times.

“In economics jargon, fiscal and banking integration are essential elements of an optimum currency area.

“An independent Scotland using Britain’s pound would be in even worse shape than euro countries, which at least have some say in how the European Central Bank is run.”

- British pound tumbles -

Markets remain on edge, as the pound slumped last week to 10-month dollar low and three-month euro troughs on fears over the impact of Scottish independence.

“They are mostly economic (concerns), with currency undoubtedly being the biggest issue” in the referendum debate, Alpari analyst Craig Erlam told AFP.

“One other issue is its membership of the European Union, which despite Salmond’s assurances otherwise, could be a big problem for them.”

European Commission President Jose Manuel Barroso angered Scottish nationalists when he warned in February it would be “difficult, if not impossible” for an independent Scotland to become an EU member.

Britain’s Conservative-Liberal Democrat government and the opposition Labour party want Scotland’s 5.3 million people to stay in the UK, arguing that the Scottish economy can prosper in the union alongside England, Northern Ireland and Wales.

Salmond claims that an independent Scotland would pursue more redistributive policies that would share the wealth of its oil revenues, while also protecting the free-to-access tax-funded National Health Service from creeping privatisation.

However, “No” campaigners say that argument is deceptive because the devolved Scottish Parliament already makes its own decisions on health policy, with the British government in London having no say.

If Scots vote “Yes” this week, Edinburgh would need to open negotiations with London over currency and the splitting of state debt and assets — a complex process leading up to the full independence which the Scottish government is planning for 2016.