Facebook is opening its new headquarters in London, the largest engineering hub for the company outside the US. Justin Sullivan/Getty Images

Facebook is opening its brand new London office on Monday (4 December). This will allow the social media giant to create 800 new jobs in the capital next year as the UK prepares for Brexit. The new site in central London will be the company's biggest engineering hub outside the United States.

Facebook's new 247,000 sq ft HQ in Rathbone Place, near London's Oxford Street, comes 10 years after the company set up its first London office. The seven-storied building was designed by architect Frank Gehry, who is best known for the Guggenheim Museum in Bilbao. It will accommodate the firm's engineers, developers, sales and marketing teams.

By the end of 2018, Facebook will have 2,300 people working for the company in the UK.

Nicola Mendelsohn, vice president for Facebook in Europe, the Middle East and Africa (EMEA), said the decision showed that Facebook was "more committed than ever" to the UK and supporting the growth of its innovative startups.

"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," 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 new site will also include Facebook's first dedicated in-house incubator for startups named LDN_LAB. Start-ups based in the UK will be invited to participate in three-month programmes designed to launch their businesses.

The move comes amid uncertainties surrounding the UK's exit from the European Union. However, Facebook announced its new headquarters last year after Google revealed it was building its own new site in the city.

Since the Brexit vote, several tech giants including Google, Snap, Facebook and Apple have announced plans to expand in the country.

"The UK is not only the best place to start a new business, it's also the best place to grow one," Chancellor Philip Hammond said. "It's a sign of confidence in our country that innovative companies like Facebook invest here, and it's terrific news that they will be hiring 800 more highly skilled workers next year."

The expansion also comes as Facebook faces scrutiny from UK and US lawmakers over its role in Russia's misinformation campaign in US and British politics and their elections. The UK parliament recently announced its own investigation into Russian interference and has requested Facebook and Twitter to provide evidence of the same.