Bob Diamond is due to be grilled by the British MPs today, a day after he resigned as Barclays chief executive following manipulation in inter-bank lending rates. He will give evidence to the Treasury Committee. His appearance was arranged before the latest furore, but he is likely to be quizzed about who knew what and when. Amid reports that Mr Diamond was pressured to resign, there is speculation that he will use the committee hearing to hit back at senior political and City personnel.