The Treasury Select Committee (TSC) is to appoint specialist advisers to oversee the drafting of a report by the Financial Services Authority (FSA) into the failure of HBOS.
Andrew Tyrie, chairman of the TSC, has written to FSA chairman Lord Turner, telling him he expects the report to assess the regulator's own conduct and the reasons for the failure.
As with a previous report into RBS, the TSC-appointed advisers will be responsible for ensuring the final text is a fair and balanced reflection of the evidence.
Tyrie said: "Work on the report should begin immediately. It must be comprehensive, covering the reasons for, and consequences of, both the Lloyds/HBOS merger and the earlier Bank of Scotland/Halifax merger.
"The public deserves to know exactly what happened at HBOS. The Treasury Committee will ensure that this happens."
The FSA yesterday confirmed it would start work on a report into the HBOS failure after it issued former executive chairman Peter Cummings with a £500,000 fine and a life ban from the financial services.
HBOS was taken over by Lloyds Banking Group in 2008 after a run on its shares.
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