Sushi is now outselling the most popular brands of sandwiches in some of Britain's supermarkets, the country's second-biggest supermarket chain said Thursday.

Sainsbury's PLC said an increasing number of its customers are turning to sushi, and in some stores it is actually more of a favorite than sandwiches -- still the main staple of the British lunch.

A company spokesman told Kyodo News: "Sushi sales are going from strength to strength. In our Tottenham Court Road store (in central London) we now sell 10 times more sushi than prawn sandwiches -- our number-one selling sandwich.

"Sales have doubled in Scotland in the last year and sushi is now outselling our top four sandwiches put together in our Glasgow Central store," he added.

On the back of this growing demand, Sainsbury's has teamed up with YO! Sushi, a British sushi company and restaurant chain, to sell cobranded sushi at 200 of the food retailer's stores.

The two companies have developed a 1 million pound plant in Hertfordshire, a county directly north of London, to mass produce the sushi.

The plant has state-of-the-art sushi-making equipment, some of which was shipped from Japan.

The first cobranded sushi went on sale Monday, and by May it is hoped that all the stores will be stocking the new brand.

Sainsbury's also plans to develop the YO! Sushi range to include sake, Japanese beers and green tea.