Chris Packham has joined a growing campaign against Pret A Manger after the food-to-go chain pushed back a pledge to phase out fast-growing chicken breeds.

The naturalist said he would not “set foot” in Pret’s cafés until the business produces what campaigners describe as a credible plan to stop using so-called “frankenchickens”.

Pret committed in 2018 to stop using fast-growing chicken breeds by 2026 as part of the Better Chicken Commitment, a welfare framework covering breed, stocking density, lighting, enrichment and slaughter standards.

However, campaign groups Anima and Project Slingshot have criticised the chain after it extended its timeline to 2032.

The groups have launched a £1m public campaign against Pret, which they said has already attracted 40,000 signatures.

Packham said: “I am absolutely furious at Pret for breaking their promise to chickens.

“Factory farming has broken the chicken. Bred to grow so fast that they can barely walk, scrabbling around in their own waste, broken bones and deformities. The life of a fast-growing chicken is hell. It’s a horror story dressed up as a lunch menu. It’s absolutely unacceptable.”

He added: “That’s why I’m joining the campaign to hold Pret to account. I’m taking a break from Pret, and I won’t be setting foot in their cafes until they produce a real, credible plan to stop selling frankenchickens, just like they promised to do eight years ago.”

The protest is the latest in a series of actions targeting Pret over its chicken sourcing policy.

Packham was pictured alongside a four-metre animatronic “Frankenwrap”, a campaign prop that has toured Pret cafés in London and attracted more than 10m social media views, according to organisers.

Campaigners argue that Pret is presenting itself as committed to higher welfare while failing to move quickly enough on the central issue of breed.

Packham said: “It was bad enough when KFC, Nando’s and Burger King withdrew their commitments to stop selling frankenchickens. But what Pret are doing is equally insidious.

“They’re pretending to be committed to ending their use of frankenchickens whilst doing nothing about it. I’m not falling for it. When a company is committed to making a change for animals, they don’t wait 14 years to do it.”

Pret has previously said it remains committed to implementing the Better Chicken Commitment, despite extending its roadmap.

The chain’s updated plan sets out an ambition to reach 50 per cent slower-growing breeds by 2031 and full adoption by 2032.

Pret has also argued that it is one of the few major foodservice operators still working towards phasing out fast-growing breeds, after several restaurant chains stepped away from the Better Chicken Commitment earlier this year.

Animal welfare groups have become increasingly focused on the use of fast-growing broiler chickens, which have been bred to reach slaughter weight quickly.

Supporters of the Better Chicken Commitment say slower-growing breeds can improve welfare outcomes, while foodservice operators have raised concerns about supply, cost and environmental trade-offs.

The dispute puts Pret under renewed pressure at a time when consumers are scrutinising the welfare and sourcing standards behind everyday food-to-go products.

For campaigners, the issue is now not just whether Pret remains signed up to higher-welfare goals, but how quickly it can show measurable progress.

For Pret, the challenge will be balancing animal welfare expectations with commercial realities across a supply chain that depends on chicken for many of its best-known sandwiches, salads and wraps.

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