A video grab from footage broadcast by the UK Parliament's Parliamentary Recording Unit (PRU) shows Government whip Mark Spencer as he stands at the dispatch box and speaks to announce the business of the House of Commons for the following week, in the House of Commons in London on May 23, 2019 AFP
Here is the timetable ahead for Britain's prime minister as Theresa May prepares to step down from the role:
May 24: Theresa May announces her intention to resign as leader of the governing, centre-right Conservative Party and therefore as prime minister.
May 26-27: Results of Thursday's UK elections to the European Parliament revealed. Opinion polls put the newly-formed Brexit Party on course to win. The Conservatives could finish as low as fifth.
May 28: Informal dinner of EU heads of state or government in Brussels to discuss the outcome of the European Parliament elections and start nominating the new heads of the EU institutions. May is expected to attend.
May 29: Date on which May will have lasted longer in office than the last Labour prime minister, Gordon Brown, who was in Downing Street from 2007 to 2010. She would become Britain's 35th-longest-serving prime minister out of 54.
June 3: US President Donald Trump begins his three-day state visit to Britain.
June 4: House of Commons returns from its break.
June 5: Prime minister and Trump due to attend a major military ceremony in Portsmouth on the southern English coast, from where ships left for D-Day landings 75 years ago in the largest seaborne invasion in history.
June 6: Main D-Day commemorations in Normandy, northern France.
June 6: Peterborough by-election. A marginal seat which the Conservatives would, in normal circumstances, hope to win. The Brexit Party is looking to cause a major upset and win its first seat in parliament here.
June 7: May will formally resign as leader of the Conservative Party.
June 10: Process to elect new Conservative Party leader is expected to start this week. May will remain as prime minister until the process is complete.
June 20-21: European summit in Brussels. EU leaders will decide on who will take the big jobs in the EU institutions for the next five years and to adopt the EU's strategic agenda for 2019-2024.
June 28-29: G20 summit in Osaka, Japan. Britain's prime minister due to attend.
July 2: Inaugural plenary session of the new European Parliament. It was hoped that Britain, even if it took part in the elections, would be out before this point so the MEPs would never actually take their seats.
July 11: Third anniversary of May becoming leader of the Conservative Party.
July 13: Third anniversary of May becoming prime minister.
August 25-27: G7 summit in Biarritz, southwest France. British prime minister due to attend.
September 29-October 2: Conservative Party conference in Manchester, northwest England. The new party leader will be in place and address their main annual gathering.
October 17-18: European summit in Brussels. British prime minister due to attend if UK is still in the EU at this date.
October 31: Barring a third postponement or an earlier departure, Britain leaves the European Union.