REGIME CHANGE, IT'S WHAT WE DO:

Inflation is running at more than 8 per cent, but food inflation is even higher, and there has been panic buying of buckwheat, a Russian staple that is served as a side dish or cooked into soups, pancakes or porridge. Prices have risen by up to 80 per cent in some regions. Rice is more than 25 per cent more expensive than it was last month, and the retail price of pasta is expected to climb by a similar degree.

Sergei Guriev, a former ­adviser to Prime Minister Dmitry Medvedev and a former board member of Russia's largest state bank, said: "If nothing changes, if sanctions aren't removed and the price of oil does not go up, then in two years the Russian government will have a major problem -- it will lack cash and it will not be able to borrow it."

Speaking from Paris, where he fled after state harassment left him fearing for his freedom last year, Dr Guriev said that rising ­inflation, the depressed oil price, the falling rouble, isolation from Western capital markets and plummeting investor confidence meant that, for the first time, "there is a risk to the existence of the regime".

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