Britain's Ambassador to the EU Tim Barrow (L) shakes hands with European Council President Donald Tusk after handing him the British prime minister's formal notice of the UK's intention to leave the EU under Article 50 of the Lisbon Treaty in Brussels on March 29, 2017. 
Britain launched the process to leave the European Union on March 29, saying there was "no turning back" from the historic move that has split the country and thrown the bloc's future into question. / AFP PHOTO / POOL / YVES HERMAN        (Photo credit should read YVES HERMAN/AFP/Getty Images)