Sky News has learnt that the Treasury is to publish guidelines within days setting out expectations for banks' future provision of cash deposit and withdrawal services.

One source briefed on the plans said the City minister, Andrew Griffith, would make a policy statement building on a government announcement in May last year.

Under the new rules, the Financial Conduct Authority (FCA) will have powers to fine banks that fail to provide free access to cash.

Personal current account-holders would not be allowed to face hidden fee charges for withdrawing cash under the rules.

Millions of people continue to rely on cash, even as Britain's payments industry becomes increasingly dominated by digital services.

The closure of thousands of bank branches since the 2008 financial crisis has stoked fears that those in vulnerable groups face being cut adrift without guaranteed cash access.

In recent years a number of pilot schemes have been launched to provide shared access to banking hubs for customers of different banks.

Mr Griffith is understood to have visited one of these in Brixham, Devon, earlier this week.

It was unclear how the new three-mile rule would apply to rural communities across the UK.

Nigel Farage, the former UKIP leader whose treatment by NatWest subsidiary Coutts has sparked a political furore over "debanking", is understood to have gathered hundreds of thousands of signatures for a petition aimed at halting the reduction in cash services by banks.

The Treasury refused to respond to several requests for comment.