Transaction fees is one the major revenue source for MasterCard and includes authorization, settlement and switchcharges as well as connectivity charges.
You could also switch your balance to a credit card which charges a lower rate of interest - there are many providers of these special "balance transfer" deals.
Ministers know they need to switch the burden of tax from fuel to direct charges such as motorway tolls or urban congestion charging, but fear voters' reaction.
Consumers should vote with their feet and switch to a different supplier if their power company raises its charges, Energy Secretary Chris Huhne has said.