The three wealthiest Japanese finance houses are set to step into the worsening sub-prime carnage as the "silent investment partners" of Wall Street and Europe's stricken banking titans. Senior sources at the "big three" Tokyo megabanks told The Times that they had readied a combined cashpile of as much as $10 billion (£5 billion) and were open to negotiation with any struggling Wall Street bank that approached them for a cash infusion. Mitsubishi UFJ (MUFJ), Mitsui Sumitomo Financial Group (SMFG) and Mizuho Financial – banks that have been scarred only very lightly by the sub-prime crisis in the United States – are understood to have already opened preliminary talks with several American firms. One MUFJ insider said that his firm was planning to compete directly with the leading Asian sovereign wealth funds as a long-term investor in the troubled American banks.