The banknote producers share price tumbled 17.5p this week to a three-year low of 218.5p.

Paul Jones, an analyst with Numis Securities, believed that De La Rue still had to resolve the production of new banknotes, which had posed problems with their additional security features.

In a best-case scenario its sliding down a slippery slope, he added. In the worst case its falling off a cliff edge.

De La Rue head of corporate affairs Mark Fearon said there was bound to be speculation since it had already issued two warnings.