Pret A Manger will roll-out a wireless internet service across its entire store network in a bid to increase product sales.

Wireless internet access available to customers using Wi-Fi enabled devices has already been implemented in 60 of Pret's 160 branches. The roll-out follows a trial in April which demonstrated that customers remained in-store for longer and spent more on food and drinks.

It is expected that the service, implemented by supplier The Cloud, will be made available in all stores during December.

"Everything we do at Pret is about delighting our customers. By offering Wi-Fi free we are giving our customers that little bit extra," said Simon Kerry, head of IT at Pret A Manger.

"The benefit is that our customers are happier and that they stay with us for longer."