European Council President Donald Tusk holds British Prime Minister Theresa May's formal notice of the UK's intention to leave the bloc under Article 50 of the EU's Lisbon Treaty that was delivered to him by Britain's ambassador to the EU, during a press conference in Brussels on March 29, 2017. Britain formally launches the process for leaving the European Union on Wednesday, a historic step that has divided the country and thrown into question the future of the European unity project.(Photo/Agencies)
