Facebook opened its new London office on Monday and said it would add another 800 jobs in the capital next year, underlining its commitment to Britain as the country prepares for Brexit.
The investment, which makes London the biggest engineering hub for Facebook outside the United States, was welcomed by finance minister Philip Hammond, who was given a tour of the new building located off the main shopping thoroughfare of Oxford Street.
"It's a sign of confidence in our country that innovative companies like Facebook invest here," he said.
Facebook announced the new investment in November last year, shortly after Google said it was building a new hub in the city that will be able to accommodate more than 7,000 employees in total.
The twin announcements were seen as a vote of confidence in London's future as a technological hub despite the decision to leave the European Union which has thrown Britain's future trading relationships into doubt.
"The UK's flourishing entrepreneurial ecosystem and international reputation for engineering excellence makes it one of the best places in the world to build a tech company," EMEA vice president Nicola Mendelsohn said.
"And we've built our company here - this country has been a huge part of Facebook's story over the past decade, and I look forward to continuing our work to achieve our mission of bringing the world closer together."
The site will also house Facebook's first in-house start-up incubator, called LDN_LAB, designed to help kick start fledgling British digital businesses.
"The emphasis on engineering and the 800 new jobs being created shows London remains at the forefront of global innovation," London Mayor Sadiq Khan said in a statement.
"What's more, the launch of the company's incubator is set to play a crucial role in attracting vital talent to London and will help to pave the way for the next generation of successful start-ups."
The new jobs, which come 10 years after the company set up its first London office, will take Facebook's total British workforce to more than 2,300 by the end of 2018, it said.
Facebook's new office in the capital's West End, designed by architect Frank Gehry, will house engineers, developers, marketing and sales teams working on products like Workplace, its business product which was built in London, it said.