Firms that benefited from government furlough cash should have their names published, MPs have urged.
The Public Accounts Committee called on the Treasury to set out new transparency guidance for government support in the next six months.
The committee repeated its earlier warning that fraud and error in government Covid schemes may have cost taxpayers billions of pounds.
But the government said it had acted "at speed" to help workers and firms.
Fraudsters could have benefited from the government's decision to drop basic checks in paying out Covid loans and furlough support, the committee said. แหล่งรวมสล็อต
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The committee said it was impossible to tell how much money had been wasted, because data issued so far had "insufficient detail to allow for public scrutiny".
For example, HM Revenue and Customs (HMRC) will not have a statistically valid estimate of how much fraud and error there was in the furlough scheme until December this year, 22 months after it began.
But the Department for Business has said the Bounce Back Loan Scheme could cost the taxpayer £27bn in fraud or credit losses, estimating that between 35% and 60% of loans might not be repaid.
Publishing a comprehensive list of companies claiming support would give transparency and an opportunity for whistle-blowers to report fraud, the committee said.