During the recent Wall Street boom years, few firms embraced commercial real estate as aggressively as Lehman Brothers.

Last year, when the firm announced it was teaming up with Tishman Speyer to buy the real estate investment trust Archstone in a $22bn deal, with Lehman providing the riskiest part of the financing, some veterans of the property market wondered if the bank really had the strength commensurate with its ambitions.