World markets failed to make gains yesterday despite revised figures showing the US economy grew quicker than previously thought between April and June.

The world's biggest economy grew at an annualised rate of 1.7%, up from a previous estimate of 1.5%, the US Commerce Department said, but the revision only served to further weaken hopes of fresh stimulus measures.

The FTSE 100 Index fell 32.2 points to 5743.5, with miners among the biggest fallers after fears about growth in China depressed commodity prices.

Market sentiment is currently being dominated by speculation about whether US Federal Reserve boss Ben Bernanke will signal more quantitative easing in an eagerly awaited speech tomorrow at the Jackson Hole symposium in Wyoming.

Hopes have waned in recent days amid a mixed picture for the US economy, and the latest improved output figure made the need for imminent action less pressing.

The Dow Jones Industrial Average in the US was flat as the London market closed, while France's Cac-40 slipped into the red, although Germany' Dax pushed slightly higher.

In London, commodities trader Glencore International was the biggest faller with a drop of 15.5p to 368.5p after a Financial Times report suggested a Norwegian sovereign wealth fund had opposed the miner's proposed $30 billion (£18bn) takeover of miner Xstrata.

The speculation piled extra pressure on Glencore after Qatar's sovereign wealth fund also demanded improved terms and threatened to vote against the deal.

Miner Rio Tinto was another major faller, down 88.5p to 2773.5p, while Anglo American was off 49.5p to 1816p.

Meanwhile, retailer Marks & Spencer continued to ease back after last week's excitement over rumours of an £8bn bid from CVC Capital Partners.

With a mixed reception to its new Cheshire Oaks flagship store launch in Ellesmere Port, the stock fell 3.2p to 359.6p.

Energy company SSE was a big top flight riser after broker Bank of America Merrill Lynch upgraded the stock to buy from neutral in the wake of its recent domestic tariff increase.

Shares were up 15p at 1372p, while British Gas owner Centrica was up by 1.9p to 329.5p.

Outsourcing firm Serco posted an 8% rise in half-year profits to £120.5m but shares were held back by ongoing concerns over the impact of challenging conditions in the US. The stock rose 3.5p to 566p.