A Conservative MP tasked with investigating the Libor rate-rigging scandal said she and her fellow politicians were "useless" in uncovering the truth behind the affair.
The admission by Andrea Leadsom, a member of the Commons Treasury Select Committee that grilled Barclays' chief executive Bob Diamond last week, raises questions about whether a parliamentary inquiry will have the rigour to reveal the truth about the banking debacle.
Speaking to The Independent newspaper, Mrs Leadsom questioned the honesty of Mr Diamond's evidence when he was cross-examined last Wednesday.
Mrs Leadsom said: "He was ridiculously unbelievable. When he said, at one point, he was 'physically ill' I felt like saying, 'Can we see the sick bucket because otherwise we're not going to believe you'. Terrible. Absolutely terrible."
Mrs Leadsom told The Independent that last week's scrutiny of Mr Diamond was hamstrung by a lack of access to paperwork, including email trails and recordings of meetings, which left the committee "batting in the dark".
She said: "I don't think we did a fantastic job either. It's a fair criticism to say 'You guys were useless'."