The government's equalities minister Harriet Harman has said the default retirement (DRA) age should be scrapped.
Harman is set to announce a fast-track review of the DRA today, but in an interview with the Daily Mail she said Britons should not be forced to work beyond 65, but should have the option to choose to do so if they wanted to.
She added workers over 65 should also be given a legal right to ask to work part-time or from home, or make a range of other variations to their hours.
The changes in the law would cover staff who have already signed contracts that say they will retire at the normal age, but will not alter the point at which the state pension can be claimed.
While employers would be able to decline the requests, they would have to give one of eight valid reasons for doing so.
Harman said: "It is a difficult thing for employers, it is challenging to business, but at the end of the day practice has to change as the facts are changing.
"The retirement age is arbitrary, it bears no relation to people's ability. Think of people running their own business – they don't shut up shop suddenly when they reach the age of 65.
"People are remaining active and healthy well into their older years. But at the moment there is no legal backing for you if you want to stay at work, so what we are proposing is a massive public policy change.
"We do want people, if they want to, to be able to stay working for longer, and flexible working is a way that enables them to do that.
"They could say they have decided they want to work three days a week and it would then be down to the employer to demonstrate why the business couldn't cope with that."
Any change in the law is also expected to include provision for employers to remove older staff who are incapable, through ill health or frailty, of maintaining performance levels.