Facebook logos are pictured on the screens of a smartphone (R), and a laptop computer, in central London on November 21, 2016.
Facebook on Monday became the latest US tech giant to announce new investment in Britain with hundreds of extra jobs but hinted its success depended on skilled migration after Britain leaves the European Union. The premier social network underlined London's status as a global technology hub at a British company bosses' summit where Prime Minister Theresa May sought to allay business concerns about Brexit. / AFP PHOTO / Justin TALLIS        (Photo credit should read JUSTIN TALLIS/AFP via Getty Images)