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)
Theresa May, U.K. prime minister, right, and Leo Varadkar, Ireland's prime minister, shake hands following a joint news conference inside number 10 Downing Street in London, U.K., on Monday, June 19, 2017. The Republic of Ireland is the Northern Ireland's biggest trading partner outside Britain. Photographer: Simon Dawson/Bloomberg via Getty Images
LONDON, ENGLAND - JUNE 19: Britain's Prime Minister Theresa May and Irish Taoiseach Leo Varadkar have 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)
