Pressure mounts on Barclays chief Diamond Bob Diamond, Barclays chief executive, should take responsibility for a "complete cultural failure" former City minister Lord Myners has argued after the bank was fined for attempting to manipulate a benchmark interest rate. Lord Myners told the BBC that the behaviour of Barclays staff was the "most corrosive failure of moral behaviour" he had ever seen in a UK financial institution. US and UK authorities have fined Barclays a record £290m for trying to manipulate the London interbank offered rate over five years and three continents. Investigations into other banks are continuing. Mr Diamond has already said that he and three of his most senior staff would waive any bonus for this year "to reflect our collective responsibility as leaders." But his pay packet might be scrutinised further when Vince Cable, business secretary, appears before a select committee to discuss executive pay later on Thursday. The Barclays chief executive could come under increased political pressure as George Osborne, chancellor, makes a statement to the Commons about the investigation at noon on Thursday. The Treasury select committee has said it plans to haul Mr Diamond, and the leadership of the Financial Services Authority, in front of the committee of MPs to discuss how the violations could have happened. Andrew Tyrie, chairman of the committee, said: "Banks were clearly acting in concert. I fear it's not going to be the end of the story, that we are going to find that other banks have been involved. Other members of the committee warned that it would be a mistake for the board of Barclays to think that paying the fine would be the end of the issue. "I don't think they should underestimate the damage this has done to their reputation and probably to banking more generally," said Pat McFadden, a Labour MP on the committee. A former chief executive at the bank joined in the criticism, saying Barclays should explain who knew about the practices. Martin Taylor, who led the company from 1994 to 1998, accused the bank of "systematic dishonesty." The question of how high up knowledge of this goes is something only Barclays can answer. I think they should answer," he told the BBC Radio 4"s Today programme. "These organisations are very large, as I know myself, and the chief executive doesn't always know everything that's happening in the organisation," he said. But somebody at a senior level somewhere will certainly have known. I can't believe Barclays haven't identified who that is.