Barclays has become the first UK high-street bank to enable customers to turn off transactions at selected retailers, including online gaming sites and betting shops.

Working with a range of partners, including the Money Advice Trust and building on research from organisations such as the Money and Mental Health Policy Institute, the bank identified a customer segment – including those with mental health issues and addictions – that would benefit from more control over how their money is spent.

A button within the Barclays mobile banking app now enables the customer to pick the types of retailers they can spend with, meaning any attempted payments in excluded categories will be automatically declined.

Marc Etches, chief executive of GambleAware, welcomed the initiative: “There are 340,000 problem gamblers in Britain and a further 1.7 million at risk, and initiatives like this can play an important role in helping to reduce gambling-related harms.

“There are no limits to stakes and prizes for online gambling, and credit cards are allowed so it is important to make it easier for people to control their spending.”

Catherine McGrath, managing director at Barclays, added: “We are always looking for new ways to support our customers and make it easier for them to manage their finances.

“This new control feature is the latest new service that we have introduced in the Barclays Mobile Banking app that aims to give all of our customers a better way to manage their money in a simple, secure and effective way.”

Martin Lewis of MoneySavingExpert, the founder and chair of the Money and Mental Health Policy Institute, said: “Mental health and debt is a marriage made in hell. Many with mental health issues struggle to control their spending – whether through gambling, shopping or premium phone lines – and I commonly hear from people with thousands of pounds of debt as a result.

“I want to applaud Barclays for being the first major bank to sit up, take note and act. I believe it will make a real difference to people’s lives and I hope the other banks will follow suit.”

As well as gambling outlets, Barclays also identified four other core retailer groups that customers can control; specifically grocery stores and supermarkets; restaurants, takeaways, pubs and bars; petrol and diesel; and premium rate websites and phone lines.

The bank said the new feature is now available to all debit card customers, and will be rolled out to credit card holders “in the near future”.