Andrew Tyrie, Chairman of the Treasury Committee, has written to some of the UK's major banks after the Committee heard evidence last month that the figures published by banks may be understating the level of fraud in the banking system.In the letter, thought to be addressed to Barclays, HSBC, Lloyds, Royal Bank of Scotland and Santander, Tyrie said the claims would be "extremely concerning" if proved true."Any data on fraud levels published by the industry should be as comprehensive as possible," Tyrie said."The public should be given the best possible information about the risk of fraud, as well as how to avoid it. Banks must be as open as possible with consumers about what this information does and does not cover."The chairman of the committee admitted that while banks were reluctant about disclosing sensible informations, the public demanded a more transparent approach."Banks are perhaps understandably reticent about disclosing information that could be used by fraudsters. But the public and consumer interest in a high level of transparency is also strong," Tyrie said."It is possible that consumers would be even more risk averse with respect to fraud were it the case that a lot more money is being withdrawn from accounts than consumers realise. The incentives on banks to clamp down on fraud need to be at least as strong as those on consumers to identify it."