Washington (CNN) The Clinton Foundation confirmed Thursday that it received as much as $26.4 million in previously unreported payments from foreign governments and corporations for speeches given by the Clintons.

It's the latest in a string of admissions from the foundation that it didn't always abide by a 2008 ethics agreement to disclose its funding sources publicly. That agreement, penned as Hillary Clinton became secretary of state, is certain to continue the headache that the foundation's work and donors have become for Clinton as she makes another run at the White House.

The Washington Post first reported the news that, since 2002, Bill, Hillary and Chelsea Clinton gave 97 speeches benefiting the foundation, earning anywhere from $10,000 to $1 million dollars in fees.

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Former President Clinton was the biggest earner for speeches, giving three that brought in anywhere from $500,000 to $1 million.

Both he and his wife gave a smattering of speeches to foreign companies and other organizations for anywhere from $250,000 to $500,000. Bill Clinton spoke to Thailand's Ministry of Energy, China Real Estate Development Group, Ltd, and Qatar First Investment Bank; Hillary Clinton spoke to Goldman Sachs, Citibank and JP Morgan Chase, among others.

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