In an interview with the Leicester Mercury, Fisher, who sits on the BoE's Monetary Policy Committee and Financial Policy Committee for regulation of the wider financial system, was quoted as saying that the impact of a euro break up would depend on how it was handled by European authorities.

"No one is trying to anticipate a euro break-up, but you just can't rule it out," he said.

His comments come after Prime Minister David Cameron and finance minister George Osborne met with BoE Governor Mervyn King and bank regulator Adair Turner to discuss contingency plans for a possible break-up of the euro zone.

Worries about the stability of the currency zone have escalated due to worries about Spain's banking system and uncertainty about Greek elections next month.

(Reporting by Fiona Shaikh; Editing by Toby Chopra)

• A Permanent Economic Emergency