Media playback is unsupported on your device Media caption David Cameron: BP investment "is a great boost to the rest of our economy"

BP has been given the go ahead to proceed with a new £4.5bn oil project west of the Shetland Islands.

The BP-operated scheme is an extension of the existing Clair oil field, and will also include investment by fellow oil firms Shell, ConocoPhillips and Chevron.

David Cameron said the news was a "massive boost for jobs and growth".

BP said it and its partners were now investing almost £10bn in North Sea oil and gas work over the next five years.

'Maintaining production'

BP said it would use the latest technology to maximise recovery from the new Clair Ridge project.

Mr Dudley said that after a "decade of decline", industry-wide oil investment in the North Sea and the Atlantic Margin was now increasingly strongly once more.

"Although it began over 40 years ago, the story of the North Sea oil industry has a long way yet to run," said BP chief executive Bob Dudley.

"After some years of decline, we now see the potential to maintain our production from the North Sea at around 200,000-250,000 barrels of oil equivalent a day until 2030.

"And we are working on projects that will take production from some of our largest fields out towards 2050."

'Jobs boost'

It is a huge national advantage having such a brilliant oil and gas industry here in Aberdeen and here in the North Sea David Cameron, Prime Minister

The announcement of the £4.5bn Clair Ridge scheme comes after BP and its partners revealed plans earlier this year for a £3bn redevelopment of the Schielhallion and Loyal fields, also to the west of the Shetland Islands.

In addition, they are investing £700m in the development of the Kinnoull field in the central North Sea.

BP and German firm RWE are also continuing to invest £550m in the North Sea's Devenick gas field.

Taking all these projects together, BP says they will provide 3,000 jobs across the oil and gas supply chain, with the Clair Ridge scheme creating "hundreds of new jobs".

Speaking in Aberdeen, Prime Minister David Cameron said: "We live in a very dangerous and difficult world, we do not want to be over reliant on energy supplies from difficult parts of the world, from unstable parts of the world.

"And it is a huge national advantage having such a brilliant oil and gas industry here in Aberdeen and here in the North Sea.

"We should treasure that and want to see it expand, want to see it grow, want to see it be part of a good and diversified energy industry in the UK."