Axel Weber, the president of the Bundesbank, on Wednesday hit out against the Volcker rule, saying it could have "unintended and unfavourable consequences."

Weber, favourite to take over at the helm of the European Central Bank (ECB) when Jean-Claude Trichet's term expires next year, said the rule, named after its creator - former Fed chairman Paul Volcker, went too far in interfering with "activities that are perhaps more risky but not necessarily economically inefficient."

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