The prospect of a knife-edge US presidential election shook investors' confidence and sent the London market lower yesterday.

The FTSE-100 index closed 29.49 points lower at 5839.06 as President Barack Obama and Republican Mitt Romney fought a close-run battle. Germany's Dax and the Cac-40 in France were both lower.

The President and Mr Romney are running almost neck-and-neck in national polls, but pointers from many key battlegrounds show Mr Obama narrowly ahead. The sentiment was dampened further after a purchasing managers survey for the US services sector revealed a worse-than-expected slowdown in growth in October.

The pound fell against the US dollar to 1.59 as the uncertain outlook boosted the greenback's perceived status as a safe haven investment. Sterling was up against the euro at 1.24.

The poor sentiment hit miners, with Eurasian Natural Resources sliding to the bottom of the index, dropping 12.2p to 321.3p, while Vedanta Resources lost 42p at 1118p.

HSBC shares were more than 1% lower after a 51% slide in the bank's reported pre-tax profits for the three months to September 30 of £2.2 billion.

The bank set aside an additional £500 million to cover fines from US authorities for breaching anti-laundering rules, while it also took an extra £220m hit to cover customer compensation.

Shares in the lender were down 8.1p at 618p.

The wider banking sector was under similar pressure, with Royal Bank of Scotland off 4.8p at 276.5p, Lloyds Banking Group down 0.6p at 42.9p and Barclays losing 3.7p at 237.5p. Prudential shares came under pressure after the insurer entered into a long-term partnership in Thailand with Thanachart Bank.

The deal will see the Pru buy the Thanachart Life Assurance Company from Thanachart, the fifth largest retail bank in Thailand, for £358m in cash. The shares were 2.5p lower at 856p.

Weir Group was the biggest riser on the Footsie as the pumps and valves maker said it expected to report full-year profits of between £440m and £450m. The upbeat forecast came despite the group, which focuses on oil and gas markets, revealing revenue and profits growth had slowed in the third quarter due to a lower order book. The shares were ahead 80p at 1831p.

Outside the top flight, shares in low-cost airline Ryanair were 6% higher after the low-cost carrier said it expected full-year profits of £392m-£416m after a better-than-expected summer.