First minister says yes vote would boost economy, but Danny Alexander counters with promise of £1,400 'UK dividend'

The Scottish government and the UK Treasury have set out rival visions of the costs and benefits of Scottish independence.

Launching a report at St Andrews House in Edinburgh, the first minister, Alex Salmond, said an independent Scotland could generate more than £5bn a year of extra revenues within 15 years, equating to £1,000 per person, without having to raises taxes.

The report details how a yes vote in September's referendum could help boost the Scottish economy by increasing productivity, boosting the working age population and increasing employment.

Meanwhile, the chief secretary to the Treasury, Danny Alexander, projected that over the next 20 years Scots would benefit from a "UK dividend" of £1,400 per person per year from 2016-17 onwards.

Publishing a paper outlining what the UK government sees as the challenges of independence, Alexander described the Scottish government's estimate as "a bogus bonus", adding that a separate Scotland could face higher interest payments on government debts at the same time as it had to deal with declining oil revenues and an ageing population.

According to the Treasury analysis, the direct costs of independence would include higher borrowing rates for an independent Scottish state, the net costs of setting up new institutions, and the net costs of funding the policy commitments contained in the Scottish government's recent white paper.

It suggested that if the UK debt was split according to population at the end of 2015-16, an independent Scotland would take on debt of about 74% of its GDP, which could reach "unsustainable levels without policy action".

Speaking in Edinburgh, Alexander said: "Today we have shown that, by staying together, Scotland's future will be safer, with stronger finances and a more progressive society. Because as a United Kingdom we can pool resources and share risks. It means a UK dividend of £1,400 a year for every man, woman and child in Scotland. That dividend is our share of a more prosperous future. It is the money that will pay for better public services and a fairer society."

He added that, working from OBR forecasts, an independent Scotland would begin with a budget deficit double that of the UK.

The Scottish government paper says Scotland's finances in 2016-17 would be similar to, or stronger than, those of the UK and other G7 industrialised countries, with debt on a "downward trajectory", enabling future Scottish governments to start an oil savings fund.

Salmond said the paper, Outlook for Scotland's Public Finances, "gives a very clear picture of what independence could deliver in economic terms for the people of Scotland". The paper suggests that an increase of 0.3 percentage points in the long-run productivity growth rate could raise an additional £2.4bn a year in revenues by 2029-30.

Increasing the employment rate by 3.3 percentage points could provide additional revenues of £1.3bn a year, while a rise in the population, less than the UK as a whole is expected to see, could add a further £1.5bn a year to the total by 2029-30.

Salmond said: "Scotland is one of the wealthiest countries in the world, more prosperous per head than the UK, France and Japan, but we need the powers of independence to ensure that that wealth properly benefits everyone in our society. That wealth means we will start life as an independent nation with strong finances and huge economic potential."