Desperate government attempts to stimulate the economy have been criticised as "expensive experiments" by an influential group of MPs.
The Public Accounts Committee (PAC) said the Treasury did not seem to understand the risks and benefits of £375 billion of quantitative easing (QE), while its flagship lending guarantee scheme had failed.
The department was also rebuked for not getting a grip on spending across Whitehall, and "impenetrable" book-keeping.
The verdict was delivered in the cross-party committee's report into the Treasury's performance in the last financial year.
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