The global banking industry is wasting €4bn a year through inefficient use of collateral assets, according to an industry survey, at a time when banks are struggling to meet higher capital requirements and keep funding costs down.

In a report on bank collateral use, Accenture, the global consulting firm, found that as much as 15% of the available collateral on a bank's books is not being used when its posts margin, mainly due to assets such as bonds being spread across different trading divisions.