Future North Sea oil and gas revenues could be six times higher than a UK economic watchdog has forecast, according to a report.
The claim was made by N-56, which describes itself as an “apolitical business organisation”.
The UK Office for Budget Responsibility (OBR) has forecast North Sea revenues of £61.6bn between 2013/14 and 2040/41.
But N-56 said the figure could be as high as £365bn, if a series of recommendations were implemented.
N-56 was founded by Dan Macdonald, who is a member of the advisory board for Yes Scotland, which is campaigning for independence.
The Scottish and UK governments have repeatedly clashed over the future of the oil and gas industry, particularly around forecasts from the OBR on the amount of cash it expects to be raised from the North Sea.
Scottish ministers have argued that the OBR forecasts are based on a “very low estimate of future total production”, while its own figures have been criticised by opponents who claim they are overly optimistic.