The escalating crisis in Ukraine has hit the European markets, which have seen a major slump amid worries the tensions will force higher energy prices if economic sanctions come into effect.
Traders remain wary that a worsening conflict could affect Russia's supply of oil to the EU, two thirds of which is piped through Ukraine.
Oil prices surged by around 2% to above 104 US dollars a barrel in New York while the FTSE 100 Index was off by more than 1.5% at below 6700.
Other leading European markets suffered bigger falls, with the Dax in Frankfurt down by more than 2.5%.
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The 270 victims of the Lockerbie bombing have been remembered today, 26 years to the day that they lost their lives in the air disaster.
Actress Billie Whitelaw, who starred in films including The Omen, has died aged 82.
Scotland's top prosecutor and an FBI director met to discuss the progress of further investigations into the Lockerbie bombing.