An official report in Britain has suggested that a large quantity of highly-enriched uranium may have been mislaid over a three year period at the Dounreay nuclear plant on the north coast of Scotland in the 1960s.

The study, by the UK Atomic Energy Authority, found that one-hundred and seventy-kilograms of the material couldn't be accounted for from a waste shaft which is due to be emptied.

The missing uranium would have been enough to make a dozen nuclear bombs.

The Authority says the missing material may be explained by failure at the time to log the correct amounts.

But the Scottish National Party has called for a full inquiry.