The two women allegedly used the sensitive insider information to ‘almost double their money' by buying and selling shares in one company.

Ammann, who worked at the London offices of Japanese bank Mizuho, was one of only seven at the bank who knew that global electronics company Canon was planning a takeover of Dutch printing firm Oce.

The German banker allegedly shared this sensitive information with his two lovers – who had no knowledge of  each other – months before the deal became public. Weckwerth, 44, made nearly £2million while Mang, 29, pocketed £60,000 from their illicit trading, it was claimed.