The price of Brent crude oil prices has fallen below $50 (£33) a barrel for the first time since May 2009.
Benchmark Brent crude futures fell more than a dollar to $49.92 a barrel this morning, later rising back above $50.
Analysts said that further price falls were likely because of an excess of supply and sluggish demand
Shippers, airlines and motorists stand to gain from the fall.
Bank of England governor Mark Carney said last month that the oil price slide was a "net positive development" for the UK.
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