“Central banks have come to the party and said ‘look, we’re really concerned about growth; we’re going to take steps to boost the economy, or support the banking system,” said Michael Hewson, analyst at CMC Markets.
“I think that tells investors that there is some sort of consensus forming,” he said.
Financials were among the top gainers. Prudential lurched almost 12 per cent to the top of the FTSE 100 leader board, while Standard Chartered and Lloyds Banking Group enjoyed near nine per cent gains.
The FTSE 100 closed up 189.09 points, or 3.7 per cent, at 5,291.26, eradicating losses sustained in the first two trading days this week.
Miners gained in tandem with base metals as investors took heart from US data that hinted at an improvement in the labour market.
Antofagasta and ENRC, up 10.2 per cent and 9.7 per cent respectively, were the top performers in a sector which has lost almost a third of its value in 2011.
Industrials IMI and Weir Group, sensitive to the economic cycle, enjoyed respective gains of 11.5 percent and 6.6 percent.
Elsewhere, brewer SABMiller jumped seven per cent, in volumes more than four and a half times its 90-day daily average, on Brazilian press reports that Anheuser-Busch InBev is set to make an $80bn move on the brewer.
On the downside, Man Group slipped 1.2 per cent, topping the blue-chip fallers’ list, in the wake of the hedge fund manager’s recent disappointing trading update.