"I am delighted to be joining Facebook. After almost 20 years in European and British politics, this is an exciting new adventure for me," Clegg wrote on his Facebook page.

Clegg said Facebook was "at the heart of some of the most complex and difficult questions we face" such as "privacy of the individual", "integrity of our democratic process", and "the balance between free speech and prohibited content".

"I believe that Facebook must continue to play a role in finding answers to those questions -- not by acting alone in Silicon Valley, but by working with people, organisations, governments and regulators around the world to ensure that technology is a force for good.

"I am looking forward to being part of this endeavour," he said.

The Press Association news agency and the Financial Times said Clegg would be Facebook's new head of global affairs and communications and would move to California in January.

The 51-year-old is also a former European Commission trade negotiator and member of the European Parliament.

- Campaign to stop Brexit -

Clegg used to be head of the Liberal Democrats, a small opposition party, but was voted out of parliament in a 2017 election when the party suffered major setbacks.

The former politician has pushed for a second referendum that could stop Brexit but the proposal has been ruled out by Prime Minister Theresa May.

His most recent book is entitled: "How to Stop Brexit (And Make Britain Great Again)".

"As someone who has spent a lifetime arguing for Britain's wholehearted commitment to Europe, it is of course a wrench to be leaving the public debate at a crucial time in the Brexit process," Clegg wrote on Friday.

"But the key decisions will soon pass to Parliament, of which I am no longer a Member, and once I had decided to take up this unique new challenge at Facebook, I felt it was best to get going sooner rather than later," he added.

Clegg speaks Dutch, French, German and Spanish, and joined the government after a 2010 election campaign characterised by "Cleggmania" over his superior performance in television debates.

He was badly damaged, however, by going back on a promise not to raise university tuition fees once in government.

The social network has faced several public relations crises in recent months and has instituted changes, particularly on privacy and the transparency of political campaign ads.

In October, it admitted that up to 29 million accounts had been breached by hackers.

It was also criticised for its handling of a data privacy scandal after it emerged that a British company called Cambridge Analytica had used data gathered through an app on Facebook to target voters in the US presidential election in 2016.

The company, along with other social media giants, has also been accused of allowing "fake news" to spread that manipulated public opinion ahead of Donald Trump's victory in that election.

dt/zak/nla

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