Several of the MPs who questioned Bob Diamond last week are now considering calling him back for a second session of questioning because they are dissatisfied with his answers.

Andrea Leadsom, who was part of the inquiry team in Bob Diamond’s questioning, admitted that the Select Committee was nowhere close to the truth behind the Barclays banking scandal. Leadsom complained that she found parts of Diamond’s evidence “simply unbelievable”, while John Mann, another Labour member of the committee, said that he “may not have been entirely honest in his answers”.

She said, “We had great weaknesses in that we didn’t have email trails. We didn’t have recordings of the morning meetings where you could point to what had been said. All we really had were the regulators’ reports, what we’d seen in the media.” Leadsom’s remarks will raise further doubts about whether the larger parliamentary inquiry being set up to investigate the banking scandal will be able to uncover the whole truth.

David Cameron has rejected Labour’s calls for a judge-led inquiry, arguing that it would take too long. Paul Tucker, the Deputy Governor of the Bank of England, will be questioned by the same committee today about the now-infamous telephone call he had with Diamond at the height of the banking crisis in 2008. Any clash between his evidence and Diamond’s will add to the pressure for the former Barclays head to be recalled.

Tomorrow, the Treasury Select Committee will question the outgoing Barclays chairman, Marcus Agius, about the state of mind of executives who thought it was acceptable to rig interest rates. He can also expect to come under pressure not to allow Diamond his full pay-off, estimated to be £17 million.

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