Sir Deryck Maughan, who was forced out as chairman and chief executive of Citigroup International after a run-in with Japanese regulators, has joined buy-out firm Kohlberg Kravis Roberts as managing director and chairman of the firm's new business in Hong Kong and Tokyo.

Maughan, who had overall responsibility for Citigroup's private banking operations in Japan, was ordered to go by Chuck Prince, chief executive of Citigroup, after Japan's Financial Services Agency claimed to have found evidence of "illegal" profits arising from deals in areas ranging from overseas property to arts treasures and closed the business.