Visa holds a 67.6 percent share of the European market for payment cards, with MasterCard taking 27.7 percent, which the complaint says constitutes a "collective market dominance." The anticompetitive effects of their refusal to process WikiLeaks donations amounts to discrimination between customers and distorts competition, which places DataCell at a competitive disadvantage, the complaint says.

DataCell has tried to find other companies to partner with in order to process MasterCard and Visa transactions, but to no avail. Telus told DataCell that MasterCard and Visa have prohibited other companies from working with it, DataCell's complaint says. As a result, DataCell's business has been seriously damaged since it relies on the payment card processing system for its customers to purchase its services.

A Visa spokeswoman said the company had received a letter about the action but had no further comment. MasterCard did not have a comment. Sveinsson said he had not heard yet from either company.

Sveinsson said WikiLeaks is also preparing two civil lawsuits, one to be filed in Iceland and the other in Denmark. The civil suit in Iceland will seek compensation from the card companies, he said. The suit in Denmark will allege breach of contract between DataCell and Teller.

If the situation between MasterCard and Visa does not change, those suits will likely be filed later this year, as courts in Iceland and Denmark are not in session due to the summer holidays, Sveinsson said.