Bob Diamond has angrily rejected suggestions that he misled MPs over regulators' concerns about activities at Barclays.

The bank's former said the claims were "totally unfair and unfounded" - and indicated he was ready to appear before the Commons Treasury Select Committee again to defend his reputation.

The rejection of the claims came in a letter sent following an evidence session with Barclays chairman Marcus Agius. He wrote: "Having watched the committee's session I was dismayed that you and some of your fellow committee members appeared to suggest that I was less than candid with the committee last week. Any such suggestion would be totally unfair and unfounded."

During the dramatic session, Mr Agius disclosed that Mr Diamond was "voluntarily" waiving a potential £20 million in deferred share bonuses. But the ex-chief executive will walk away with a £2 million package, made up of a year's salary and pension cash contribution, after quitting.

Mr Agius - who has signalled he will step down after a replacement for Mr Diamond is found - admitted that Barclays' relationship with the regulator was "strained".

The MPs cited a letter from the Financial Services Authority (FSA) flagging the regulator's concerns about "a pattern of behaviour" in which Barclays sought to gain advantage through the use of complex structures which are "at the aggressive end of interpretation of the relevant rules and regulations".

Committee chairman Andrew Tyrie and other members insisted the evidence contradicted what they heard from Mr Diamond, who denied knowing that regulators were concerned.

"Many of us when we heard that last week thought that his replies were implausible but didn't have evidence to support that hunch," Mr Tyrie told BBC News. "Today we began to collect quite a bit of evidence to suggest that Bob Diamond's presentation of what happened was quite a long way away from what really happened."

Labour member John Mann said Mr Diamond had "serially misled" Parliament on a range of issues. He said it was the majority view of the committee that Mr Diamond should be recalled. Mr Mann - who is also pressing for Mr Diamond to donate his £2 million pay- off to charity - added: "There's a question of the reputation of Parliament."

In his letter responding to the allegations, Mr Diamond stressed that he had not been questioned about the period when the FSA had raised concerns, in April this year. "I trust this addresses any concerns you may have had," he went on. "The comments made at the hearing have had a terribly unfair impact upon my reputation, which is of paramount concern to me. I look forward to discussing this issue with you further if you wish to do so."