The chief economist of Citigroup has launched a scathing attack on the G20 as a decision-making organisation, claiming the global body has "no legitimacy and no competence."
Willem Buiter, speaking in Brussels on Thursday, expressed concern that heads of state were using G20 conferences to make decisions on issues that they know little about.
"On the competency side, the heads of state make statements [but] haven't really got a clue," he stated.
"Anyone who whines enough can get in - it's a self-hired club of the most powerful nations but does not speak for the people," in reference to the attendance of Spain at the last four G20 summits, separate to their EU representation.
Buiter, who was speaking at the ninth Annual European Financial Services Conference, recommended that the International Monetary Fund provide a permanent secretariat to the G20 to set agendas.
The outspoken economist, who became chief economist in January 2010, also rounded on the European system of governance, which requires unanimity between the regulators of member states to agree changes. He compared it to a "circus".
"The inability to do anything at all should be taken as a given. If anything comes out then it's really a small miracle.
"Getting anything through Europe is extremely difficult because it is such a maverick experiment, and hopefully there will be nothing like it in the future.
"It's very difficult to walk with 27 legs - I've tried," he quipped.
Buiter also took issue with the appointments to the European Systemic Risk Board being "overweight" with central bankers, instead of being balanced with more regulators.
Article compliments Global Financial Strategy