Douglas Peterson, Citigroup's top man in Japan, today made a humiliating mea culpa to Japanese politicians over the scandal which prompted regulators to shut the group's private banking operations.

Three months ago a report from the Financial Services Agency, Japan's most senior regulator, said that the bank's hunger for profits at the expense of compliance led to it being used by outside criminal elements for a number of scams including potential money laundering and stock market manipulation.