LONDON, ENGLAND - JUNE 19: Britain's Prime Minister Theresa May (R) and Irish Taoiseach Leo Varadkar shake hands at a joint press conference after talks at 10 Downing Street on June 19, 2017 in London, England. The new Irish Taoiseach said he had been reassured about a potential deal between the Conservative Party and the Democratic Unionist Party (DUP) after raising concerns about the deal with the Prime Minister. (Photo by Philip Toscano - WPA Pool/Getty Images)