AN INDEPENDENT Scotland could create a new, more efficient tax system which would help boost the economy, according to a Scottish Government panel of economic experts.

In a report yesterday, the Government's Fiscal Commission said moving away from the UK tax system would be challenging and take time.

However, the experts insisted the opportunity to create a new system should be seized in the long-term, claiming: "Potentially everyone could become better off".

Their report was welcomed by Finance Secretary John Swinney but was dismissed by Alistair Darling, the head of the pro-UK Better Together campaign, who said it failed to give real answers on how much people might pay.

The Fiscal Commission's report said the Scottish Government should develop "a clear plan for how it will migrate, over time, towards the development of its own modern Scottish specific tax system" based on four key principles - simplicity, neutrality, stability and flexibility.

It said an independent Scotland could choose to depart from the UK system in the "medium to long term", defined as at least five years after the SNP's proposed formal date for leaving the UK of 2016.

In the immediate aftermath of a Yes vote it said the Scottish Government could agree "service agreements" with UK tax authorities to deliver a collection service.

The emerging new-look ­Scottish tax system, it argued, "should also take account of the economic linkages with the rest of the UK" and ensure it was simple to pay taxes in both countries.

The experts, led by former ­Scottish Enterprise head Crawford Beveridge, said the UK tax system was complex and inefficient.

They said: "Independence would provide a unique opportunity to develop a modern and efficient tax system. If Scotland was to get it right, it could be used as a powerful tool to grow key areas of the economy and tackle long-standing weaknesses.

"An efficient system could be a major international competitive advantage for Scotland supporting more investment, jobs and growth.

"Establishing such a system will be challenging and should be phased over time. However, the benefits of moving to such a system will undoubtedly pay off in the long-run."

The report suggested that "losers" from a new system may need to be compensated.

Welcoming the report, Mr ­Swinney said: "With independence we have opportunities to build on our reputation for fiscal responsibility and put in a place a framework with real credibility."

However, pro-UK campaigners claimed it left voters in the dark.

Mr Darling said: "This report raises more questions than it answers. The document says that income tax rates will change in an independent Scotland but the SNP Government is telling us nothing about exactly how much tax we would pay.

"Until the Nationalists give us an answer to the big question on tax, no-one will believe any of the promises they make."

Alistair Carmichael, the ­Secretary of State for Scotland, said: "This report contains no information about the tax rates individuals and businesses would face. The paper also completely avoids the question of which taxes would go up to fill the £3.4 billion black hole that the IFS think tanks forecasts will exist from the first year of independence.

"No Government can ­fundamentally reform a tax system without winners and losers. The Scottish Government should set out its proposals, and who would pay more alongside who would pay less."

In a separate report yesterday the Fiscal Commission confirmed an earlier recommendation for an independent Scotland to create an equivalent of the Office for Budget Responsibility to provide independent forecasts.