Until recently, men retired at 65 and women at 60. Today, neither will get a penny in state pension until they turn 66.

From 2026, the retirement age will start rising again, to 67. A decade or so after that, it will rise to 68, and will carry on climbing after that.

On current projections, future generations will have to carry on working until age 74.

Politicians have justified this by arguing that as people live longer, they'll have to work longer, too. Rising life expectancy and the falling birthrate make the state pension unaffordable.

So far, it's been a pretty convincing argument.

Not after today.

New figures from the Office for National Statistics show that average life expectancy for men and women in the UK has fallen significantly following the Covid pandemic.

Between 2019 and 2019, average UK life expectancy at birth was 79.3 years for men and 83.0 years for women

These figures have since fallen to 78.6 years for men – that's a drop of more than a year – and 82.6 years for women.

Life expectancy at age 65 has also fallen. At that age, men are set to die 22 weeks earlier than before, while women will lose on average 15 weeks.

After decades of rising life expectancy, improvements have now “ground to a halt”, said Tom Selby, director of public policy at AJ Bell.

In fact, it’s worse than that.

For decades, it's been taken as a given that life expectancy would continue increasing for each generation, due to health and medical advances.

That's no longer the case, and the pandemic isn't solely to blame.

Even before Covid struck, life expectancy improvements had pretty much stopped, Selby said. "Now they’re actually going backwards.”

Life expectancy at birth has fallen back to 2010 levels and Selby said: "This will place extra pressure on the next government to hold off on state pension age increases."

I suspect falling life expectancy is already having some effect. Last year, there were rumours that the state pension age could rise to 68 early in the 2030s.

The government decided that was too controversial, and backed off. Now the decision will be made in the next Parliament. If life expectancy continues to fall, the case will be almost impossible to make.

The state pension age is tied up with the triple lock, too.

READ MORE: State pension warning as triple lock ‘cannot last forever’

The Treasury would love to see the back of the triple lock, again, claiming it's too expensive. It was introduced to boost pensioner incomes, and it's done exactly that.

No wonder the mandarins hate it.

That's another decision that's been pushed into the next Parliament. Politicians know that scrapping the triple lock would be massively unpopular.

The danger is that if politicians cannot use rising life expectancy as an excuse to make state pension savings, they will turn to the triple lock instead.

Of course, today's figures cover the Covid years. With the pandemic largely over, life expectancy could start to resume its century-long increase.

I'm not convinced, though. Britons don't exactly live healthy lifestyles.

There is also a huge gap in life expectancy, with those on low incomes dying much earlier than the better off.

We can't keep expecting them to work into their late 60s or early 70s before qualifying for the state pension. Many will die first or before they get there, despite making decades of National Insurance contributions.

I suspect that today's figures could prove a turning point in the state pension age debate. It may not rise inexorably after all, and hurrah for that.

I still fear for the triple lock, though.