Which? magazine has criticised plans that will force sports fans buying tickets or merchandise at the 2012 Olympic Games to use Visa payment systems.

According to the consumer magazine, organisers will not allow people to use Mastercard or American Express cards after Visa signed a deal with 2012 organisers to become the sole card payment provider. Which? editor Martyn Hocking said: "The 2012 Olympics should be equally accessible to all. We want the London 2012 Committee to take the steps necessary to ensure there's a level playing field and that UK consumers have equal access to the games, whether or not they are Visa cardholders."

A London 2012 spokesperson told the BBC: "Visa will be the official card and payment system for London 2012, in the same way as for the Beijing Games in 2008 and the Vancouver Games earlier this year."