The growing involvement of banks in commodities markets is finally being placed under the microscope. Next month the US Federal Reserve is expected to report on whether it will allow US banks to continue with their current involvement in the commodity markets. Its action could well prompt governments around the world to follow the lead.

Metals, energy and soft commodities are all now heavily influenced by the activities of banks: whether it is financing, physical trading, warehousing or derivatives. Most of these areas are unregulated and opaque and thus render the banks open to allegations of conflicts of interest and abuse.