Boeing is to build a £100m facility for a new fleet of spy planes based in Scotland.

RAF Lossiemouth in Moray will be the home of the new fleet of nine P-8A Poseidon military aircraft the UK Government ordered last year.

The US plane-maker said the deal will make the UK its European base for the training, maintenance, repair and overhaul of fixed-wing and rotary platforms for the firm.

It also stated the expansion plans will effectively double the number of people it employs in the UK to around 4000.

Boeing also pledged to increase the bid opportunities it offers to UK suppliers in an attempt to double their work with the manufacturer.

The P-8A Poseidon planes, announced as part of the Strategic Defence and Security Review last November, will replace the UK's fleet of Nimrod surveillance aircraft which were based at RAF Kinloss until they were scrapped in 2010.

Prime Minister David Cameron said: "I want the UK to continue to be at the forefront of the global aerospace industry, both civil and defence.

"That's why I'm delighted that we can announce today a long-term strategic initiative with Boeing that will create thousands of jobs, secure investment in R&D and create opportunities for the supply chain, as well as delivering on our defence commitments.

"Boeing is one of the world's most respected aerospace companies. This long-term commitment shows the UK is open for business, and attractive for investment."

Boeing chairman Dennis Muilenburg said: "Boeing is committed to the UK Government's prosperity agenda and we share the goals of enhanced economic growth that the Prime Minister has set out to us."

Moray MP Angus Robertson, who represents Lossiemouth, said: "This is really good news, which follows years of campaigning to end the gap in UK maritime patrol capability and save the Lossiemouth base from closure by the Tory government.

"It was sheer folly to scrap the Nimrod fleet without a working replacement, leaving the UK as the only northern European air force without maritime patrol aircraft.

"This gap is being closed, which is hugely welcome and thanks need to be extended to everyone who has been fighting Lossiemouth's corner to secure this announcement.

"Alongside many others in Moray I campaigned vociferously against the base closure and against the scrapping of the Nimrods. The strategic geographical importance of RAF Lossiemouth is clear for all to see and that is being reflected with the expansion of the base's role."