In afternoon deals, Europe's main stock indices were down over one per cent, while Wall Street also opened on the down side.
Asian bourses also buckled on news that China's exports plummeted last month, as anaemic global demand hit the world's second-largest economy, while weak imports fuelled worries about crucial domestic appetite.
However, troubled Samsung Electronics staged a slight recovery on bargain-buying after losing about 10 per cent of its value this week on the Galaxy Note 7 crisis.
"The drop in China's trade surplus, which included a surprise fall in imports, meant the basic resource sector which has a big exposure to Chinese commodity demand was dragging the UK equity benchmark lower," said CMC Markets analyst Jasper Lawler.
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"Shares of Rio Tinto and BHP Billiton were top fallers today, but are still up in a week that has seen domestically focused shares come under pressure because of the weaker pound.
In Europe, "shares of Tesco and Unilever... Both dropped as investors became alarmed over a dispute on prices", Lawler added.
A seemingly Brexit-fuelled spat between British supermarket giant Tesco and Dutch food and consumer goods multinational Unilever erupted today.
Unilever, which makes popular household brands like Marmite yeast extract spread, Flora margarine, PG Tips teabags and Persil washing powder, wanted major price hikes due to the Brexit-driven slump in sterling -- which it said has ramped up the cost of imported materials.
That prompted Unilever to halt deliveries to the company, sparking a shortage of its branded goods on the supermarket's shelves, while the hashtag #MarmiteGate trended on Twitter.