Boris Johnson has not voted for himself despite a heavy tactical campaign to oust him from his Uxbridge and South Ruislip seat.
The prime minister instead broke with a tradition set by his predecessors having registered to cast his ballot in Westminster.
He voted at Methodist Central Hall, near Downing Street, at about 8.15am. His local Tory candidate in the constituency of Cities of London and Westminster Nickie Aiken is facing a strong threat from Liberal Democrat Chuka Umunna, who left the Labour Party earlier this year.
Johnson took his Uxbridge and South Ruislip seat with a 5,034 majority at the snap election two years ago but pro-European Union campaigners have urged Remainers to unite behind Labour’s Ali Milani in a bid to topple the former London mayor.
When the ex-journalist was elected to the seat in 2015, he was living in Islington.
Traditionally prime ministers have voted in their own constituencies.
On polling day in 2017, then-prime minister Theresa May voted in her constituency of Maidenhead and David Cameron had his say in Witney in 2015.
At the general election in 2010, Gordon Brown turned up to his local polling station in North Queensferry, situated in the Dunfermline and West Fife constituency he resided in and next to his own seat of Kirkcaldy and Cowdenbeath.
Tony Blair also voted with his family at a polling station in his constituency of Sedgefield, County Durham, in 2005, even though he had been in Downing Street for eight years by that point.
The Tory leader turned up to the polling station in Storey’s Gate, a street overlooked by Westminster Abbey, with his dog Dilyn in tow.
Labour leader Jeremy Corbyn voted at 9.30am with wife Laura Alvarez in Islington North, where he lives and has represented as an MP since 1983.