[U.K.] Cabinet minister Ed Balls spent thousands of pounds of taxpayers' money attending a private meeting of one of the world's most powerful and secretive organisations. Mr Balls, widely regarded as Gordon Brown's closest adviser, travelled to Canada for the four-day conference of the shadowy Bilderberg Group of businessmen and politicians when he was Economic Secretary to the Treasury. The cost of the trip, in air fares, hotel bills and expenses is estimated at up to 5,000. The group's rules insist that all participants attend in a private and not an official capacity". However, a Treasury spokesman said Mr Balls had attended "in his capacity as a minister" and confirmed that all expenses had been met from public funds. Also at the event with Mr Balls ... were the former American Secretary of State Henry Kissinger and David Rockefeller, the American banker and philanthropist. Participants at Bilderberg, named after the Dutch hotel where its first conference took place, have been described as the "shadow world government". It was founded ... in 1954. Critics claim that it wields enormous influence in shaping world events. The group meets annually amid strict security. It has no permanent secretariat. Instead, an anonymous steering committee of two people from the 18 countries taking part sends out invitations to about 120 of Europe's and North America's leading politicians, economists, industrialists, and royals. Journalists are not permitted to cover the event, no minutes are published, and all those invited must promise not to reveal any of its agenda.