The world’s biggest coffee chain says its new code of conduct – which also addresses harassment and bans smoking and outside alcohol – aims to make its stores more welcoming.

“Implementing a Coffeehouse Code of Conduct… is a practical step that helps us prioritise our paying customers who want to sit and enjoy our cafes,” a Starbucks spokesperson told BBC News.

“These updates are part of a broader set of changes we are making to enhance the cafe experience as we work to get back to Starbucks.”

The company said the new rules would be displayed at every store and staff would be instructed to ask anyone who violates the code of conduct to leave. That includes allowing employees to call the police when necessary.

The change ends a policy Starbucks introduced in 2018 after two black men were arrested at one of the company’s stores in Philadelphia.

The men, one of whom had asked to use the toilet, had said they were waiting for a friend and refused a manager’s request to leave.

The video of the incident went viral, and critics accused the chain of racial profiling and called for a boycott.

Starbucks apologised to the men, agreed a settlement, and to help counter the backlash announced it would welcome people into their cafes, whether or not they were customers.

Starbucks has been trying to boost flagging sales as it grappled with a backlash to price increases and boycotts sparked by the Israel-Gaza war.

Brian Niccol, who previously headed the Mexican food chain Chipotle, was brought into Starbucks last year to help turn the business around.

Mr Niccol has been trying to improve the customer experience at Starbucks’ cafes by revamping its menus and coffee shops.

Other changes set to be introduced later this month include offering one free refill of hot or iced coffee for customers who buy a drink to consume on the premises.