Coffee chain Starbucks is closing more than 8,000 company-owned stores and offices on Tuesday to facilitate racial bias training.

The company says the "learning session" will focus on "race, bias and the building of a diverse welcoming company."

It follows an incident in Philadelphia last month, in which two black men who were arrested.

The men were asked to leave the store, before being arrested for 'trespassing'. No charges were filed against the pair.

The incident was captured on video and shared on social media, prompting protests and calls for a boycott of the coffee chain.

The company has since apologised and reached a settlement agreement with the two men.

Starbucks executive vice president for US retail, Rossann Williams, told staff: "Our hope is that these learning sessions and discussions will make a difference within and beyond our stores.

In this file photo, Rashon Nelson (left) and Donte Robinson (right) listen to a reporter's question during an interview with The Associated Press in Philadelphia | Image: Jacqueline Larma/AP/Press Association Images

"After May 29, we will make the curriculum available to the public and share it with the regions as well as our licensed and business partners."

"May 29 isn’t a solution, it's a first step."

The firm has worked with advisers and experts to come up with a curriculum and new technology being deployed to stores.

Starbucks says: "Each store will receive a tool kit which will allow for partners to learn together in small self-guided groups.

"This first training will focus on understanding racial bias and the history of public accommodations in the United States, with future trainings addressing all aspects of bias and experiences."

While Starbucks is closing all company operated stores, it says most of its 7,000 licensed outlets - such as those operated by major supermarkets, hotels, universities or airports - are expected to remain open.