Christopher Flowers, the ex-Goldman Sachs partner whose private equity firm is one of the bidders for Northern Rock, has returned to invest in the company that made his name.

JC Flowers is leading a group of investors that have bid Â¥202bn (€1.2bn) for a 32% stake in Shinsei Bank after shares in the Japanese lender slumped 44% on Â¥8bn losses related to sub-prime securities.