Tesco is launching what it claims is the world's first musical sandwich.

The sandwich plays a medley of Christmas tunes when the packaging is opened.

It features the same technology used in talking greetings cards.

"The concept of musical sandwiches is something we've been looking at for a while now and we thought Christmas would be the perfect time," said Tesco spokesman Jonathan Church.

"If they prove to be as successful as we think then we will consider a whole range of musical sandwiches.

"One idea already under consideration is working with record companies to launch songs by new artists on the market by way of the musical sandwich."