The bank rules are now legally binding, following an announcement from Gordon Brown.
The Banking Code has now been made legally binding, meaning that UK financial firms are to operate under tougher regulations.
Gordon Brown announced the move yesterday, adding that the newly-statutory set of rules for banks would be enforced by the Financial Services Authority (FSA). The regulator retains the power to fine firms who breach its rules.
For its part, industry group the British Bankers' Association (BBA) revealed that it had been in talks about the move with the watchdog and the government for "some months".
Angela Knight, chief executive of the BBA, said: "The codes have served their purpose well in bridging the gap between what comes under the remit of the FSA, and credit which does not. Many different entities provide lending to people and to businesses and clearly these need to be included in any new legislative requirements.
"In addition, banks will continue to follow the small business Statement of Principles which sets out the good practices that banks will follow with their small business customers in difficult times."
The Banking Code obliges banks to treat their customers fairly. For example, under its terms, financial firms are obliged to let customers know when they enact changes affecting their accounts, such as raising or lowering interest rates or overdrafts.
A new Banking Bill, unveiled at yesterday's State Opening of Parliament, also contains plans to regulate banks more toughly. The proposed legislation would make it easier for the authorities to bail out banks in danger of collapse, as well as strengthening their obligations to customers.
