European and Asian markets were sharply lower on Tuesday as sentiment was hit by escalating tensions in Libya and an earthquake in New Zealand's second-largest city which has killed at least 65 people.
London's leading index of shares was almost 60 points, or 1%, lower to sit at about 5,955 shortly after opening.
Meanwhile, the French Cac was down 0.9% and the German Dax declined almost 0.5%.
In Asia, Japan's Nikkei index, Hong Kong's Hang Seng and South Korea's Kospi were all trading about 2% lower.
Markets were hit by the continuing unrest in Libya and the Middle East, which has sent oil prices to a two-and-a-half year high.
Elsewhere, an earthquake in New Zealand and a decision by Moody's Investors Service to cut the outlook for Japan's Aa2 bond rating to negative from stable also weighed on prices.
New Zealand's prime minister says at least 65 people have died after the 6.3-magnitude earthquake hit Christchurch this morning.
John Key said the toll was expected to rise further, adding: "We may be witnessing New Zealand's darkest day."
The country's NZX 50 stock index fell 0.7% on concerns the damage caused by the earthquake will further add to the country's growing debt.
In London, BAE Systems, International Consolidated Airlines Group, Burberry Group, Royal Bank of Scotland Group and Smiths Group were all trading more than 2% lower.
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