Julian Metcalfe, the co-founder of Pret A Manger, is drawing up plans to challenge the fast-food behemoths by turning Itsu, his sushi bar chain, into a concept that will offer “fast food with a conscience”.

Mr Metcalfe, who retains an interest in Pret after its sale last year to Bridgepoint Capital, is to relaunch Itsu’s trademark sushi menu and expand it with a range of rice, vegetable and noodle-based dishes starting from £2. Although the chain of 23 outlets — all in London — will retain the Itsu name and its Far Eastern accent, the emphasis will be on providing a healthy and high-quality alternative to the big fast-food chains.

In an interview with Peach Report, a new pub and restaurant industry e-zine, Mr Metcalfe said that he was aiming to target consumers “who care about what they eat”, adding: “The food coming out of the big fast-food chains is chilling. Someone has to try to move fast food forward.”

Although Itsu’s sushi is perceived to be quite expensive, Mr Metcalfe told The Times: “It works very well, but if you want to challenge the big boys of fast food you’ve got to create something exciting and think beyond sushi.”

He added: “The question is, can anybody challenge the fast food giants, or is it going to be burgers for ever?”

But Mr Metcalfe, who in 2001 controversially sold a 33 per cent stake in Pret to McDonald’s, admitted that it would not be easy to achieve his goal of selling high-quality food at fast-food prices. “It was core with Pret, but it caused untold difficulties with sourcing, delivering every day and controlling cost and price.”

Menu items will include free-range chicken, freedom farm-reared shredded pork and prawns, as well as vegetables such as beansprouts, spinach, asparagus and edamame beans. Dishes will be served with rice or noodles and a broth made of fresh ginger and lime juice.

The first Itsu to be converted to the new format will open in the City early next year. Once the concept is established, Mr Metcalfe plans to seek joint venture partners who will provide the muscle to develop the chain across the country.

Itsu, which briefly had a store in New York three years ago, shot to prominence in November 2006 when it became mixed up in the Alexander Litvinenko poisoning affair. The Russian spy was poisoned with the radioactive element polonium before going to eat at the Piccadilly branch of Itsu.

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