A decline in sales of Aston Martin's luxury sports cars since it floated on the London Stock Exchange in October 2018 has put the company's shares and finances under sustained pressure, forcing it to seek help.

Under the deal announced on Friday, Stroll will pay 182 million pounds for a 16.7% stake which could rise to 20% upon completion of the company's plan to raise a total of 500 million pounds, including a rights issue from exiting shareholders.

Aston Martin shares surged as much as 30% after the announcement and were 18% higher at 1038 GMT.

The brand, which is mainly owned by Italian and Kuwaiti private equity groups, has come late to the lucrative sports-utility vehicle (SUV) market and has struggled to keep up with rivals owned by major global carmakers.

Aston Martin had also held talks with Chinese carmaker Geely, which makes Volvos, but it wanted to instigate more fundamental change than the plan outlined on Friday, a person familiar with the talks told Reuters.

Aston Martin Chief Executive Andy Palmer said the consortium led by Stroll, who is behind the Racing Point F1 team and owns a fleet of vintage Ferraris, will bring several benefits.

"He brings with him his experiences and access to his Formula One team," Palmer told Reuters.

"We've talked a lot in the past few years about wanting to be clearly rooted in luxury and obviously Mr Stroll knows an awful lot about luxury."

Stroll will join Aston Martin's board as executive chairman, replacing Penny Hughes, who will step down.

Under Friday's agreement, Racing Point will become the Aston Martin F1 works team from the 2021 season. Stroll's 21-year-old son Lance joined Mercedes-powered Racing Point last year from Williams and has Mexican Sergio Perez as team mate.

Stroll, who made his money through investing in fashion brands such as Tommy Hilfiger and Michael Kors, has been involved in Formula One and motor racing for years and also owns Canada's Mont-Tremblant circuit in Quebec.

'DEMAND OVER SUPPLY'

Carmakers of all sizes are using alliances, partnerships and mergers as ways to share the cost and challenge of meeting new emissions regulations, electrifying model ranges and competing on new technologies such as autonomous driving.

The car sector has been hit by a decline in sales in China and a slump in diesel sales in Europe, prompting several automakers to post disappointing results, but Aston has also suffered as a small player.

Rivals such as Bentley, which is owned by Volkswagen, and Rolls-Royce Motor Cars, a subsidiary of BMW, benefit from being part of major carmaking companies as they can share costs and expertise.

But despite more stringent emissions rules coming in over the next few years, Aston Martin said plans to invest in electric vehicles will now be delayed beyond 2025 as part of cost-cutting measures.

The consortium led by Stroll is likely to include several other people such as JCB Chairman Anthony Bamford, entrepreneur Andre Desmarais, Michael de Picciotto, telecoms investor John McCaw and Hong Kong fashion sector investor Silas Chou, all of whom have worked with Stroll before.

"I look forward to working with the board and management team... to continue to invest in the development of new models and technologies and to start to rebalance production to prioritise demand over supply," said Stroll.

(Reporting by Costas Pitas; Editing by James Davey and David Clarke)

By Costas Pitas