The extension of the scheme comes as bank branch staff worked with the police to stop £19 million of fraud in the first half of 2020, according to the latest figures from UK Finance.

Under the Protocol, police are called to the branch to investigate suspected fraud and arrest any suspects still on the scene.

£19.3 million of fraud was prevented and over 100 arrests were made through the scheme between January and June 2020. The latest figures mean the scheme has prevented victims losing a total of £116 million of fraud and led to 744 arrests since it was first introduced three years ago by UK Finance, National Trading Standards and local police forces.

A range of scams that trick elderly and vulnerable customers into withdrawing cash from their branch have been prevented, including courier scams, romance fraud and rogue traders. Customers helped through the initiative are typically aged 65 or above, with some over 100 years old.

Branch staff are trained to spot the warning signs that suggest someone may have fallen for one of these scams and make an emergency call to the police. 3,250 calls have been made in the first six months of this year through the scheme, including 637 in June.

T/Commander Clinton Blackburn, from the City of London Police, says: “Banks are often the first point of contact when someone is about to fall victim to fraud, so the banking protocol is a vital way of protecting vulnerable victims and preventing criminals from taking advantage of them.

To build on the success of the scheme, discussions are currently underway with local police forces over expanding it to telephone and online banking. This would enable bank staff at call centres to notify police when certain attempted bank transfers are being made which they believe may be the result of a scam, in situations where the customer is unable to visit their local branch to enable further checks.