Almost £90bn was added to the value of leading shares on Monday as investors breathed a huge sigh of relief that Citigroup had been rescued by the US government.

The FTSE 100 enjoyed its biggest ever daily percentage gain and its second best points gain in its 24-year history, surging 372 points, or 9.8 per cent, to 4,153. That eclipsed the 8.4 per cent rise on the day in September when the Financial Services Authority banned short selling of financials.