BP was given a shares boost today after the group announced a "giant" oil discovery in the Gulf of Mexico.
The find was made at BP's Tiber well, which was drilled to a depth of more than 35,000 feet - making it one of the deepest wells ever drilled in the oil and gas industry, according to the firm.
It is now looking to verify the size and potential of the oil discovery, made around 250 miles south-east of Houston, Texas.
BP shares raced 4 per cent ahead at one stage, making it one of the day's biggest risers in a difficult session for the FTSE 100 Index.
The Tiber well find marks the firm's second major discovery in that area of the Gulf of Mexico.
Andy Inglis, chief executive of BP exploration and production, said the two finds helped "support growth of our deepwater Gulf of Mexico business into the second half of the next decade".
Tiber well is operated by BP, which has a 62 per cent stake, with co-owners Petrobas and ConocoPhillips respectively holding 20 per cent and 18 per cent stakes.
The group first made an oil discovery in this area of the Gulf of Mexico in Kaskida in 2006.
Although this is also still under appraisal, BP said it believes Kaskida has a three billion barrel capacity and confirmed the new find was potentially in "the same league".
It has launched a number of big oil developments in the wider Gulf of Mexico over the past 15 years, including Horn Mountain in 2002, Mad Dog in 2005 and Thunder Horse last year.
Thunder Horse is seen as BP's flagship project in the region, but was hit by a number of engineering problems that delayed the launch of production by three years.
However, Thunder Horse is now running at full operation, and production is now approaching 300,000 barrels of oil equivalent a day.