THE initial cost of establishing an independent Scotland would be around £200 million, according to an academic.

London School of Economics professor Patrick Dunleavy was commissioned by the Sunday Post to research the costs involved in a Yes vote.

His report does not attach a total price tag to setting up a new state because he said transition costs will depend "very heavily" on how both the UK and Scottish governments approach the negotiations.

He estimates that immediate set-up costs to duplicate core Westminster functions will be £200 million, but "hundreds of millions of pounds more" will be needed to build the government IT systems for a new state.

The Treasury has previously estimated this would cost £900 million, which Prof Dunleavy said "does not seem implausible".

The academic said Scots may face up to a decade of transition following a Yes vote, paying a fee to continue to share some agencies such as the DVLA until 2022.

The government of an independent Scotland would require 27,000 civil servants and an increase in the number of cabinet ministers to 15, he said. The report was said to have been compiled following discussions with First Minister Alex Salmond, his deputy Nicola Sturgeon, Scottish Government economists and Treasury officials. A Treasury paper recently put the set-up costs of an independent Scotland at £1.5 billion.

Mr Salmond accused Westminster of "trying to cook the books" when analysis released in advance of its publication had cited a possible cost of £2.7 billion - a figure Mr Dunleavy has said is "bizarrely inaccurate".

The professor of political science and public policy at LSE said: "We can say with some confidence that Scotland's immediate set-up costs are likely to be constrained - we suggest around £200 million in one-off costs to create its own versions of a few but big and important existing UK department capabilities.

"The UK Treasury has suggested that Scotland could also face IT and new administration costs in taxation and benefits, of perhaps as much as £900 million. But these would be systems that come on line only in 2018 to 2021, and they would endure for many years."