Britain's top share index sank to its lowest closing level in six weeks on investor concern about the effect a further reduction of US monetary stimulus would have on emerging markets.
Investors have been on edge in recent days as unease about slowing Chinese growth and the withdrawal of US monetary stimulus spread from emerging market currencies to the world's big stock markets.
There was a mood of uncertainty on the London market as the FTSE 100 Index endured a rollercoaster day's trading - gaining at first before dropping heavily and later recovering some losses to end 28 points down at 6544.3.
It comes after fears over emerging markets saw falls on Friday and Monday, with a hiatus on Tuesday before the top-flight returned to negative territory.
Early gains had come after Turkey's decision to hike borrowing rates in order to shore up the value of the lira, but attention soon returned to the US and the prospect that policymakers would continue to tighten monetary policy.
Markets in France and Germany were also lower, and New York's Dow Jones Industrial Average was in the red too at the close in London.
On currency markets, the pound was flat, at 1.66 against the dollar and 1.21 against the euro.
Mining stocks provided some impetus for the London market after production updates from two leading players in the sector.
Chilean miner Antofagasta jumped 6%, or 50p, to 872.5p as it reported a record year of copper production in 2013, driven by a strong final quarter.
It was a similar story from Anglo American, following higher output in the three month period for iron ore, copper and diamond production. Shares surged nearly 6%, or 77p to 1420.5p.
Barclays shares were also higher, up 1.6p to 275p, amid reports that chief executive Antony Jenkins was considering branch closures in the UK and the loss of hundreds of investment banking jobs.
The bank later denied that it had plans to announce significant reductions to its branch network, though it admitted there would be fewer traditional branches in the future.
Elsewhere, shares in ITV rose 1.1p to 197.7p after it announced the launch of a new pay-TV channel dedicated to drama shows.
ITV Encore will be available to Sky subscribers.
Meanwhile, shares in Mulberry slumped 27%, or 245.5p to 654p, after the handbag maker blamed poor UK sales over the Christmas period for a substantial miss to profits expectations.
The biggest FTSE 100 risers were Antofagasta up 50p to 872.5p, Anglo American up 77p to 1420.5p, Fresnillo up 30.5p to 781.5p and Randgold Resources up 130p to 4235p.
The biggest fallers were William Hill down 10.5p to 330.5p, BSkyB down 22.5p to 844.5p, United Utilities down 18p to 719p and Prudential down 30p to 1244p.