She has been at the centre of a string of high-profile deals, but none bigger than the stake in RBS she is reportedly working on.

Amanda Staveley, 38, was born in Yorkshire and returned to her former school last year with a simple message for pupils: "Attempt the impossible."

The advice came from a good source – Ms Staveley is one of Britain's most successful businesswomen and is valued on the Sunday Times Rich List at more than £100 million.

After leaving Cambridge University because of a family bereavement, she opened a restaurant near the horse- racing mecca of Newmarket at the age of 23. It was here that she met a number of very rich, and very influential, Arab racehorse owners.

Ms Staveley is now held in high regard for her business contacts in the Middle East.

She helped rescue Barclays from a Government bail-out by forging a £3.5bn deal with Sheikh Mansour bin Zayed al-Nahyan of Abu Dhabi, and also worked on Sheikh Mansour's acquisition of Manchester City football club in 2008.