Citigroup has reported a net loss of $9.83 billion (£5 million) for the last three months of 2007.
The loss is the first at America's largest banking group since its creation in 1998 and sees revenues for the fourth quarter drop 70 per cent to $7.2bn.
The loss is claimed to have been caused by exposure to risky debt, including bad mortgage debt and subprimes amounting to $18.1 billion.
Chief executive Vikram Pandit took over from Charles Prince who resigned in December amid mounting subprime losses.
