Outgoing Prime Minister Theresa May waves to the world's media beside husband Philip May from outside 10 Downing Street on July 24, 2019 in London, England. Theresa May has been leader of the Conservative Party since 13th July 2016. Today she makes her final statement to the country as British Prime Minister. Boris Johnson, MP for Uxbridge and South Ruislip, was elected leader of the Conservative and Unionist Party yesterday receiving 66 percent of the votes cast by Conservative party members. He is due to take the office of Prime Minister this afternoon.