The SIFI designation has been adopted in other nations, through the Basel Committee on Banking Supervision.

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The Financial Stability Board released its list of 29 global systemically important financial institutions (SIFI) on Friday, confirming which banks will be required to maintain capital buffers over and above those of smaller competitors under Basel III requirements.

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If, as Mr Sants implied, the new G-SIFI capital increment settles at around 3%, that will be significantly less than the optimal level calculated by David Miles of the Bank of England's Monetary Policy Committee in an influential paper.

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Bank of America, Bank of New York Mellon, Citigroup, Goldman Sachs, JPMorgan Chase, Morgan Stanley, State Street and Wells Fargo are all on the initial SIFI list, along with four banks apiece for the U.K. and France, two from Germany and Switzerland, and a smattering from other countries in Europe.

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