LONDON, ENGLAND - APRIL 25: Shadow Secretary of State for Exiting the European Union Sir Keir Starmer delivers a speech on Labour's Brexit policy at the Institute of Civil Engineers on April 25, 2017 in London, England. Labour today outlined its plan for Brexit, which includes guaranteeing the the rights of EU workers in the UK, ahead of the June 8 general election. (Photo by Jack Taylor/Getty Images)
LONDON, ENGLAND - APRIL 25: Shadow Secretary of State for Exiting the European Union Sir Keir Starmer delivers a speech on Labour's Brexit policy at the Institute of Civil Engineers on April 25, 2017 in London, England. Labour today outlined its plan for Brexit, which includes guaranteeing the the rights of EU workers in the UK, ahead of the June 8 general election. (Photo by Jack Taylor/Getty Images)
LONDON, ENGLAND - APRIL 25: Shadow Secretary of State for Exiting the European Union Sir Keir Starmer delivers a speech on Labour's Brexit policy at the Institute of Civil Engineers on April 25, 2017 in London, England. Labour today outlined its plan for Brexit, which includes guaranteeing the the rights of EU workers in the UK, ahead of the June 8 general election. (Photo by Jack Taylor/Getty Images)
LONDON, ENGLAND - FEBRUARY 24: (L-R) Shadow Foreign Secretary Emily Thornberry, Shadow Chancellor John McDonnell and Shadow Secretary of State for Exiting the EU Keir Starmer attend a press conference on Brexit at 2 Savoy Place on February 24, 2017 in London, England. The Labour Leader Jeremy Corbyn spoke at this pre-arranged event after last night's by-elections in which Labour lost their Copeland seat to the Conservatives, an area they had controlled for 80 years. They held on to Stoke-on-Trent Central but with a reduced return of 2.2%. (Photo by Jack Taylor/Getty Images)
Keir Starmer, U.K. exiting the European Union spokesman for the opposition Labour party, leaves after delivering an election campaign speech setting out the party's Brexit strategy in London, U.K., on Tuesday, April 25, 2017. Labour pledged to tear up U.K. Prime Minister Theresa May's Brexit strategy if it wins the June 8 general election and instead focus on keeping the benefits of the European Unions Single Market and Customs Union. Photographer: Chris Ratcliffe/Bloomberg via Getty Images
