David Cameron was the Prime Minister of the U.K. when the referendum took place. Personally, he supported staying within the EU. As the votes turned against his campaign, he stepped down as PM.
As leader of the Conservative Party, Theresa May took over from David Cameron in 2016. May promised to put Brexit into action. However, Brexit hit a roadblock for various reasons. Unable to get a Brexit divorce deal passed on Parliament, May stepped down on June 7, 2019, after a turbulent 3-year period as prime minister.
On July 23, 2019, Brexit hardliner Boris Johnson, former Mayor of London and British Foreign Minister, was elected Prime Minister. Johnson was keen on delivering Brexit by the October 31, 2019 deadline. However, Johnson needed a Brexit extension of his own after MPs failed to get the revised deal passed into law. This led to the new deadline of January 31, 2020.
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