The board at Barclays was told less than six months ago that the relationship between the bank's senior management and the City watchdog had "broken down", according to reports.
The Telegraph reports Andrew Tyrie, chairman of the Treasury Select Committee, said senior figures at the Financial Services Authority (FSA) informed the board in February that former chief executive, Bob Diamond, and his management team had 'lost their confidence'.
Tyrie also said the FSA had raised concerns about the appointment of Diamond in September 2010 and sought confirmation there would be a "change of culture" at the bank.
Tyrie is expected to write to the bank asking the letters from the FSA to be made public, the paper reported.
Has been cold-calling consumers
New shares admitted to London Stock Exchange
Slow and steady growth
Missed funding target by £240,000
Denies any wrongdoing