The government of Tony Blair has been paralysed for some time by uncertainty over the timing of his departure and the prolonged interregnum before Gordon Brown takes over, as no one any longer really doubts that he will.

Now, however, the reputation of the UK prime minister, already dragged through the dirt by the debacle in Iraq and diminished by controversies such as the suspension late last year of bribery investigations into a Saudi arms deal, is taking a battering over the cash-for-honours affair.