A large percentage of the accounting gains booked by US banks Citigroup and Morgan Stanley in the third quarter were credited to their European businesses, complicating attempts to estimate the likely performance of their European rivals.

Despite a difficult three months in the region, in which primary markets closed and secondary market liquidity dried up, both Citigroup's securities and banking unit and Morgan Stanley were able to report quarter-on-quarter revenue growth for Europe, the Middle East and Africa of more than 25% as a result of the gains.