Animal welfare campaigners marched a 400-metre petition through central London on Tuesday before delivering it to Pret A Manger’s headquarters as part of a protest over the sandwich chain’s chicken welfare commitments.

Campaign group Anima said the petition, which it described as the world’s longest animal welfare petition, was five times the length of the Bayeux Tapestry and had been signed by more than 100,000 people pledging to boycott Pret.

The protest followed criticism of Pret’s decision to delay a previous commitment to stop using fast-growing chickens, which campaigners describe as “frankenchickens”.

Campaigners claim boycott could cost Pret £3m

Anima said new analysis by Development Economics estimated the boycott could cost Pret around £3 million in lost revenue during its first year.

The figure is an estimate commissioned in connection with the campaign and does not represent a confirmed loss reported by Pret.

Campaigners argue that customers may believe Pret uses higher-welfare chicken than is actually the case.

Polling cited by Anima found that 41% of respondents expected Pret’s chickens to have outdoor access, while only around one in ten expected the birds to come from standard indoor farms.

Connor Jackson, chief executive of Anima, said: “Pret’s customers are being conned by empty promises.

“Every day people eat at Pret with expectations of high animal welfare, and yet behind their polished marketing, frankenchickens are collapsing in their own waste from leg disorders and heart failure.”

Deadline pushed back

Pret originally committed in 2018 to move away from fast-growing chicken breeds by 2026.

Campaigners say the company’s own reporting shows no progress against that target.

Earlier this year, Pret moved its deadline to 2032, a decision criticised by Anima and naturalist Chris Packham, who described it as a delay rather than meaningful progress.

Fast-growing chickens are selectively bred to gain weight rapidly, and animal welfare groups say this can increase the risk of leg problems, heart conditions and skin damage.

Open letter to Pret chief executive

An open letter addressed to Pret chief executive Pano Christou was also published in national newspaper advertisements on Tuesday.

It was signed by several animal welfare organisations, including Humane World for Animals, FOUR PAWS UK, Animal Equality UK and The Humane League UK.

Claire Bass, senior director of campaigns and public affairs at Humane World for Animals, said: “More than 100,000 people and nine animal charities have sent a clear message that we want faster and firmer progress on chicken welfare at Pret.

“While Pret has made commitments, the company is waiting too long to turn them into action.”

She added that the organisations wanted Pret to begin moving away from fast-growing chickens sooner rather than waiting several more years.

Pret A Manger has been approached for its position on the campaign and the claims made by the organisations involved.