The cards show characters from the book, and some new ones

The cards are being launched in the run-up to the release of the Harry Potter movie in November.

Nitish Doolub, 13, of Haywards Heath, West Sussex, said: "It's a very interesting game. It's quite similar to another game by the company who made it but obviously this is on a Harry Potter theme.

"It's very intriguing if you've seen the film or read the book."

Game makers Wizards of the Coast also produces trading cards based on the Nintendo cartoon character Pok�mon.

These have become a worldwide craze - in Britain, children have fought over the cards, schools have banned them and police have urged parents not to allow children out with them.

Adults too?

Wayne Charness of Hasbro, the parent company of Wizards of the Coast, said the game will appear in seven languages and will be on sale in 42 countries.

The game is based on the phenomenally successful Pokemon card game

He said: "There are some rare ones to collect and ones which will make your deck stronger."

Jo Hall, head of toys at Woolworths, said adults were likely to be caught up in the excitement of the game.

She said: "We predict that the Harry Potter trading cards will be the hottest swap in offices this summer.

"We believe that over half of sales will come from adults as competitive parents ensure that their kids go back to school with a full set."

The Harry Potter game is based on the first of JK Rowling's best selling series of novels, Harry Potter and the Philosopher's Stone.

It has 116 cards altogether, showing characters, potions, spells and creatures from the book. There are also several new creatures and spells not in the book.

Players assume the role of wizards, and try to get their opponents to discard their cards or make them disappear.

The starter pack, which includes 82 cards, costs �7.49.

There are also 11-card "booster packs", which include more advanced strategies and different cards, which will be available for �2.49.