BRUSSELS, BELGIUM - JUNE 23: British Prime Minister Theresa May (L) speaks with Spain's Prime Minister Mariano Rajoy Brey (R) ahead of a roundtable meeting at the EU Council headquarters on the second day of a two day European Council summit on June 23, 2017 in Brussels, Belgium. (Photo by Leon Neal/Getty Images)
Theresa May, U.K. prime minister, pauses during a news conference at the European Union (EU) leaders summit at the Europa building in Brussels, Belgium, on Friday, June 23, 2017. Citizens rights is one of the main issues that the EU and U.K. need to resolve before trade talks can be broached leading up to Britains March 2019 exit from the bloc. Photographer: Jasper Juinen/Bloomberg via Getty Images
Theresa May, U.K. prime minister, arrives for a news conference at the European Union (EU) leaders summit at the Europa building in Brussels, Belgium, on Friday, June 23, 2017. Citizens rights is one of the main issues that the EU and U.K. need to resolve before trade talks can be broached leading up to Britains March 2019 exit from the bloc. Photographer: Jasper Juinen/Bloomberg via Getty Images
BRUSSELS, BELGIUM - JUNE 23: British Prime Minister Theresa May leaves the stage following a press conference at the EU Council headquarters at the end of the second day of a two-day European Council summit on June 23, 2017 in Brussels, Belgium. (Photo by Leon Neal/Getty Images)
