Under plans being considered by ministers, the Government's proposed Financial Services Authority (FSA) may be given the power to insist that banks have a duty to prevent "financial exclusion".
The banking industry will attempt to head off regulation this week by announcing a new study into the problems to communities caused by the unprecedented wave of branch closures in recent years.
Ministers prefer self-regulation for the banks, but are making clear that the forthcoming Financial Services and Markets Bill could include reserve powers to insist on "local access" if no progress is made.
The FSA may be able to insist that banks at least provide an indoor cashpoint machine wherever they are planning to close a branch.
"We want them to prove they can get their own house in order. If they can't, then they may have to be forced to do so," said a ministerial source.
Nearly 3,500 bank branches have been closed since 1990 and the inner cities of Bristol, Birmingham, Liverpool and Glasgow have been particularly badly hit. More than one in four inner London areas have lost all their banks in the last nine years.
Most of the big four high-street banks, Barclays, Lloyds, Midland and NatWest, have claimed the rise of 24-hour telephone call centres, mergers, and the need to increase efficiency have given them no alternative but to close remote and under-used branches.
However, MPs from all parties have said that local bank branches are as crucial as local post offices for rural communities and the inner-city poor.
The elderly, the disabled and non-car owners suffer most from the lack of face-to-face banking, but research shows that local businesses also face a loss in turnover of up to 25 per cent following a closure.
Following pressure from MPs and the Government, the British Bankers Association (BBA) will announce this week that it is setting up an independent study into the issue.
The review will look at a range of options that may include "community banks", single outlets that would offer services for a number of banks allowing them to cut costs.
It will also examine the possibility of greater co-operation with community- based credit unions to allow the poor to start their own bank accounts.
Banks demand passports and driving licences for any account to be set up, but many poor people don't possess either and ministers want other proof of identity to be allowed.
Up to 3.5 million people in the UK do not have bank accounts and the Economic Secretary to the Treasury, Patricia Hewitt, has urged banks to tackle this.
The Financial Services and Markets Bill is currently being considered by a joint committee of both the House of Commons and Lords.
Derek French, director of the Campaign for Community Banking Services, said: "The loss of its last or only bank is a major blow to any community. What is certain is that if no action is take, the problems for consumers will increase and the banks' already tarnished image will be further damaged," he said.Reuse content