BP has started production from the giant Valhall field in the Norwegian North Sea after completing a redevelopment scheme to extend the life of the field to 2050.

Bob Dudley, chief executive of the oil and gas giant, described the Valhall redevelopment as a significant milestone for BP and an important investment in its North Sea portfolio.

"It is one of BP's most complex field expansion developments and gives Valhall a further 40-year design life with the capacity to handle 120,000 barrels of oil and 143 million cubic feet of gas per day," said Mr Dudley.