The escalator, introduced by then-chancellor Alistair Darling, increases the price of a pint by 2% above inflation, and is due to last until 2014-15.

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That lower "book" value captures a loss that the government has already absorbed on the investment: the loss is the difference between what the government paid for the shares and the market price of RBS on the days the then Chancellor, Alistair Darling, actually handed over the money for the shares.

BBC: RBS can be privatised within a year, says the bank's chairman - BBC News

But then the airwaves went eerily quiet and for an hour nothing was heard from the Chancellor Alistair Darling - an old friend of Geoff Hoon - or Home Secretary Alan Johnson - many MPs' preferred replacement.

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Its colour comes not from pollution but from mud and sunlight as the Darling slowly wends its way between narrow, steep banks to meet the Murray River and then the ocean 2, 400km south.

ECONOMIST: A land of drought