Supermarkets have long been known as one of the most popular places for single people to go out looking for a partner.

Now Sainsbury's, the large British chain, is helping its customers by giving them a chance to leave the shop with more than they bargained for - with the not-so-subtle use of "love bleepers".

The supermarket chain is testing the bleepers, already a craze in Japan, at a branch in north London, where there are a large number of single shoppers.

Shoppers key into the device their personal interests - which, naturally, can include eating, drinking and shopping as well as cinema and romance.

When two bleepers pass each other, be it at the breakfast cereals or among the fruit and veg, they automatically make a bleeping noise. And if their hobbies are compatible, the bleepers start bleeping and flashing simultaneously, loudly indicating a potential partner in the offing.

"We know that many of our regular shoppers are single and this offers them the chance to possibly find love," said Mr Matt Samuel of Sainsbury's.

"It is just a bit of fun and customers are taking it in that spirit."

If the scheme is successful, Sainsbury's will consider extending it to other stores.

The move is the latest marketing ploy in the supermarkets' battle for customers, and follows on from the singles nights launched by Asda.

Ms Mary Balfour, who owns two dating agencies, welcomed the idea. "In a big place like London, it is very hard to meet people and especially prospective partners," she said.

"It is tremendous to set up something that gets people together, and it certainly beats the other supermarket tactics of trolley-barging or asking about the ripeness of melons."