European Commission President Jean-Claude Juncker, Britain's Prime Minister Theresa May, Dutch Prime Minister Mark Rutte, Belgium's Prime Minister Charles Michel and Britain's Permanent Representative to the EU Tim Barrow attend a European Union leaders summit in Brussels, Belgium March 21, 2019.
Britain's Prime Minister Theresa May visits a bakery during an election campaign visit to Fleetwood, June 6, 2017. REUTERS/Ben Stansall/Pool
Britain's Prime Minister Theresa May greets the Crown Prince of Saudi Arabia Mohammad bin Salman outside 10 Downing Street in London, March 7, 2018.
Britain's Prime Minister Theresa May tours the Royal Welsh Winter Fair at the Royal Welsh Showground in Builth Wells, Wales, Britain November 27, 2018.
Britain's Prime Minister Theresa May welcomes King Willem-Alexander and Queen Maxima of the Netherlands to Downing Street in London, Britain, October 24, 2018.
Britain's Prime Minister Theresa May visits a bakery during an election campaign visit to Fleetwood, June 6, 2017. REUTERS/Ben Stansall/Pool TPX IMAGES OF THE DAY - RC1B2E41D630
British Prime Minister Theresa May arrives on stage dancing to Abba's 'Dancing Queen' before delivering her keynote address on the final day of at the Conservative Party Conference in Birmingham, Britain, October 3, 2018.
Britain's Prime Minister Theresa May reacts during a news conference at Downing Street in London, Britain November 15, 2018. Matt Dunham/Pool via Reuters
Britain's Prime Minister Theresa May is embraced by her husband Philip after giving her speech on the final day of the annual Conservative Party Conference in Birmingham, Britain, October 5, 2016.
Britain's Prime Minister Theresa May waits for Iceland's Prime Minister Katrin Jakobsdottir at Downing Street in London, Britain May 2, 2019. REUTERS/Toby Melville TPX IMAGES OF THE DAY - RC15EDFA1D60
Britain's Prime Minister Theresa May meets the Nishkam Trust leadership team and pupils of Nishkam Primary School in Birmingham, May 16, 2017. REUTERS/ Dan Kitwood/Pool
Britain's Prime Minister Theresa May waits for Iceland's Prime Minister Katrin Jakobsdottir at Downing Street in London, Britain May 2, 2019.
Britain's Prime Minister Theresa May reacts during the debate on extending Brexit negotiating period in Parliament in London, Britain, March 14, 2019. Image for illustrative purposes.
UK Parliament/Jessica Taylor/Handout via REUTERS
The wording on a slogan is changed after a letter fell away from the backdrop as Britain's Prime Minister Theresa May addresses the Conservative Party conference in Manchester, October 4, 2017. REUTERS/Phil Noble TPX IMAGES OF THE DAY - RC1DAD8CC480
British Prime Minister Theresa May gets into a vehicle at Downing Street, as she faces a vote on Brexit, in London, Britain March 13, 2019.
The wording on a slogan is changed after a letter fell away from the backdrop as Britain's Prime Minister Theresa May addresses the Conservative Party conference in Manchester, October 4, 2017.
Britain's Prime Minister Theresa May smiles as she listens to speeches at the Conservative Party's conference in Manchester, October 2, 2017.
European Commission President Jean-Claude Juncker, Britain's Prime Minister Theresa May, Dutch Prime Minister Mark Rutte, Belgium's Prime Minister Charles Michel and Britain's Permanent Representative to the EU Tim Barrow attend a European Union leaders summit in Brussels, Belgium March 21, 2019. REUTERS/Yves Herman TPX IMAGES OF THE DAY - RC12A83CC630
Britain's Prime Minister Theresa May talks with resident Val Lay during a visit to a housing estate in North London, Britain November 16, 2017.
Britain's Prime Minister Theresa May and European Commission President Jean-Claude Juncker attend the European Union leaders informal summit in Salzburg, Austria, September 20, 2018.
German Chancellor Angela Merkel and British Prime Minister Theresa May address a news conference following talks at the Chancellery in Berlin, Germany July 20, 2016.
European Council President Donald Tusk and Britain's Prime Minister Theresa May talk as they arrive for a group photo at the ASEM leaders summit in Brussels, Belgium October 19, 2018.
Britain's Prime Minister Theresa May grimaces during her speech on Brexit in London, Britain May 21, 2019. Kirsty Wigglesworth/Pool via REUTERS.
Britain's Prime Minister Theresa May speaks at the annual Conservative Party Conference in Birmingham, Britain, October 2, 2016.
British Prime Minister Theresa May leaves after a news conference following an extraordinary European Union leaders summit to discuss Brexit, in Brussels, Belgium April 11, 2019.
Britain's Prime Minister Theresa May waits for the result of the vote in her constituency at the count centre for the general election in Maidenhead, June 9, 2017.
Theresa May's tumultuous tenure