In a speech today, Martin Wheatley (pictured) will say fund managers are “stretching the definition” of rules on what can be charged to clients, costing customers an extra £3bn a year.

The FCA is to begin consulting next month on how to reform such regulations, according to the Financial Times.

The regulator’s research has found up to £500m worth of dealing commission may have been used to access the head of corporations last year.

“The way the model is currently working is, because it is bundled, you are effectively spending your client’s money when you buy access or research,” Wheatley told the FT.

“We think people would be more focused and more diligent if the fund manager was spending their own money.”

The FCA’s move leads to the possibility asset management firms will have to account for research from their own resources, or add it the headline annual management charge disclosed to clients.

The FT added Wheatley will also warn wider reform may be needed in order to ensure transparency across all areas of fund charging.