Massive shadow bank lending to firms in Asian economies could be storing up the next global financial crisis, according to former Prime Minister Gordon Brown.

Brown today warned economists may not be able to work out the extent and direction of liabilities if a credit crunch begins in Asia.

A crisis could be fomented by the “big problem” of “industrial and commerical lending in the the shadow banking sector”, Brown said. “The next crisis will not just be a re-run of the last.”

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Firms in economies across Asia have taken on debt to sustain fast growth that many economist fear may be unsustainable.

“If that crisis emerged, would we really know who owed what to whom, and on what terms?” Brown asked. “Do we really have the global data now that allows us to make the judgement about stability across some of those markets?”

While China might have the brute force to fight a crisis because of the size of its reserves, other nations would be more vulnerable, Brown warned.

He called for more cooperation among the G20 group of major economies to push forward financial stability in a coordinated manner, pointing to his own experience of diminishing willingness to cooperate as head of the G20 in 2009.

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Brown was speaking today at the Bank of England’s conference to mark 20 years of independence, a decision he himself took on becoming chancellor in 1997.

While Brown congratulated the Bank on its performance over the past two decades, he warned financial sector regulation still needs to be adjusted to be able to provide the best response to the next crash.

Brown recommended a joint strategic committee between the Treasury and the Bank to formalise working together during crises, saying there remains a problem of “underlap” in the responsibilities of the twin centres of British economic policy.

He also suggested the Financial Policy Committee, the Bank of England body responsible for the stability of the financial system, should write open letters to the Treasury suggesting areas in which fiscal policy could contribute towards stability objectives.

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Full story: Gordon Brown warns next financial crisis could come from Asia: City A.M.