One in four people aged 16 to 64 say they are disabled. And one in ten gets money from the government to help them with a disability.

But we’re not talking about physical ailments. The UK’s welfare bill is soaring because of a massive increase in the numbers saying they suffer from mental health conditions such as anxiety, depression or autism.

It’s a trend that began with the Covid pandemic. Nobody’s quite sure what caused it, or why it continues now that lockdowns are a thing of the past.

But the country can’t afford it.

For the UK’s new Prime Minister, it represents a huge problem. Andy Burnham is about to take over a Government which has no money to spare, but is committed to spending billions more on defence.

Sir Keir Starmer announced plans to increase funding for the armed forces by £15 billion over four years, but only explained how around £10 billion of this will be paid for. Mr Burnham and his new Chancellor will have to find the rest.

The new Prime Minister has also promised to spread economic growth and opportunity to regions outside London, a laudable aim but one that will cost money even if it pays off in the long run.

And the Government is also struggling to cope with the soaring cost of social care, and funding for special needs education.

Where will all this money come from? Sir Keir and his Cabinet believed that cutting the welfare bill was part of the answer. But their attempt to reduce the soaring cost was thwarted by angry Labour backbenchers, who saw it as an “attack” on disabled people.

Back in 2025, Liz Kendall, the Work and Pensions Secretary at the time, warned that the cost of benefits paid to working age people because of sickness and disability had risen by £20 billion since the Covid pandemic and would reach £70 billion a year by the next general election (for context, the UK spends around £95 billion on education and £39 billion on defence).

Referring to Personal Independence Payments (PIP), a benefit that helps disabled people with living expenses, she said: “Every day, there are more than 1,000 new PIP awards.”

She was attempting to win support for plans to make it harder to claim the benefits – which the Government admitted would only make the bill rise more slowly. It wouldn’t even get the numbers down.

But this was too much for Labour MPs. Left-winger Diane Abbott said the policy would have “catastrophic effects”. Richard Burgon called it an “immoral, appalling plan”.

And Rachel Maskell said: “I fear, like many do, that people will take their lives, once again crushed by a system that fails to believe and points the finger rather than offering the hand, turning hope to despair”

The Government backed down, and instead asked Work and Pensions Minister Stephen Timms to carry out a review.

Mr Timms published some interim findings earlier this month, but his final report comes in the autumn – when it will be Andy Burnham’s problem.

And problem is the right word. PIP is a non-means-tested benefit intended to help people cope with extra costs they face because they are disabled or have a long-term health condition. Most of us would instinctively feel this is only fair.

But something strange is happening. There were two million people receiving Personal Independence Payments (PIP) in 2019. By April 30 this year, the number had risen to four million. It’s currently going up by 300,000 every year.

The increase isn’t caused by more people having bad backs. Four in ten new claimants have what’s called a psychiatric disorder, including anxiety, depression, autism or a mood disorder.

In theory, PIP is not an unemployment benefit, and you can receive it if you work. But in practice, fewer than one in five recipients have a job.

And there is a consensus among policy-makers – if not among Labour backbenchers – that access to disability benefits makes it easier to drop out of the workforce.

Alan Milburn, the former government minister leading an inquiry into young people, has warned that a broken benefits system helps explain why so many are stuck in their bedrooms, scrolling on their phones and apparently unable to get a job or college place.

Once you get on benefits, you’re often there for life. Mr Milburn’s report, published in May, said: “Today around seven in 10 young people claiming a health and disability benefit are still claiming a decade later. The damage done to the life chances of these young people is almost incalculable.”

There are currently a million young people aged 16 to 24 not in employment, education or training – the so-called NEETS. Reforming the benefits system is essential in order to save them from a lifetime of misery, according to Mr Milburn, although he stresses that schools and the skills system also need changes.

Pat McFadden, the current Work and Pensions Secretary, said this week: “The proportion of young people being signed off sick is a major cause for concern. And that is not only about numbers but about benefit stickiness – the amount of time people spend on these benefits once on them.”

Campaigners representing people with disabilities are, understandably, determined to fight any suggestion that claimants are “scroungers” or abusing the system. The challenge for the Labour leadership is how to explain that there is a real problem without provoking a backlash, and risking another massive rebellion by backbenchers.

One way or another, Mr Burnham will need to find a way to balance the books. The UK is in so much debt that the Treasury spends £110 billion every year just on paying interest. There is no money to spare.

Taxes have risen, and the Government now collects around 40% of the UK’s total economic output in tax revenue, a figure last seen in the 1980s. There’s not much juice left to squeeze out of working people.

Ending the inexorable rise in the benefits budget must be part of the answer. But it remains to be seen whether Mr Burnham is willing to take on his own MPs to achieve it – or whether he could win the fight if he does.