Tackling unemployment linked to long-term illness will unlock economic growth that’s “hiding in plain sight”, former John Lewis chair Sir Charlie Mayfield has said.

More than 250 of the UK’s biggest employers, including British Airways, Tesco, Royal Mail, and several government departments, have signed up to his Get Britain Working taskforce.

The group aims to prevent people dropping out of work due to ill-health and encourage those signed off to come back, with official figures showing the issue costs the UK £212bn a year.

However, some employers have said previously that tax rises mean many firms cannot afford to invest, while others have warned against pushing ill people into work.

The companies signed up will track sickness absence, return-to-work outcomes, and disability participation, which the government said would make workplace health performance visible for the first time.

Many big UK businesses, including Sainsbury’s, EDF Energy, and Currys, as well as 10 mayoral authorities, including London and Manchester, have agreed to take part.

Sir Charlie told the BBC: “I can’t tell you how many people I’ve met who said: ‘I was signed off work for three months, or six months, and I never had any contact with my employer at all.’

“That’s not because the employer is a bad person. It’s because we’ve got a situation at the minute where people don’t talk to each other when they really need to.”

Sir Charlie’s comments come as pressure grows on Andy Burnham, who is widely expected to take over as prime minister later this month, to reduce the UK’s welfare bill to free up money elsewhere.

According to government figures, total welfare spending in Great Britain is forecast to be 23.6% of the total amount the government spends in the 2025 to 2026 financial year.

Sir Charlie said his plans could help cut that bill.

“Fixing these problems at the fundamental level, could make a really big contribution to getting this economy working better — for employers, for employees, for the taxpayer, for all of us.”

He added: “This is not a zero-sum game. It’s not a question of employers win and employees lose and vice versa. Everybody can win.”

Sir Charlie suggested Burnham would back his plans.

“I can’t see any reason why he wouldn’t because of what Andy has said about good growth. If this isn’t good growth, I’m not sure what is, quite frankly.”

He said getting people back into work who are currently not working due to ill-health would be a simple way of boosting the workforce.

“You wouldn’t have had to build a single house, open a new channel of immigration, you wouldn’t have to wait for a cohort of young people to join the workplace. This is basically growth hiding in plain sight.”