Boris Johnson to move into bigger Downing Street home with girlfriend, leaving Sajid Javid and four children smaller flat at No 10

No 10 confirms that Carrie Symonds will join Mr Johnson in Downing Street

Boris Johnson and his partner Carrie Symonds are set to move into a four-bed flat in Downing Street, leaving Sajid Javid and his family with the smaller flat above No 10.

The new prime minister and his girlfriend will take the more spacious apartment above No 11, leaving the two-bed flat above his official residence for the chancellor, his wife Laura and their four children.

Tony Blair started the trend for moving into the No 11 flat, as he had a larger family than his chancellor, Gordon Brown. David Cameron also chose the bigger apartment to accommodate his family.

No 10 confirmed that Ms Symonds would join Mr Johnson in Downing Street but insisted there won’t be any additional cost to the taxpayer from her presence.

The prime minister’s official spokesperson said: “The PM is officially moving in today and, yes, his partner will be living there.”

Despite speculation that Mr Johnson may have needed new furniture to be paid for by the state, the spokeswoman said “there’s no cost to the taxpayer”.

Ms Symonds, a former communications director for the Conservative Party, will not have any publicly funded staff working for her, unlike Samantha Cameron, who had administrative support and a personal stylist funded by the taxpayer.

The pair will be the first unmarried couple in Downing Street in living memory, as Mr Johnson is undergoing divorce proceedings with his second wife, Marina Wheeler.

Ms Symonds watched the prime minister’s first speech in Downing Street alongside staff but she did not accompany her partner through the famous black door on his first day in office.

Their relationship has come under major scrutiny after neighbours called the police over a late-night row at Ms Symonds’s Camberwell flat during the Tory leadership contest.

In a recording of the incident, which was leaked to The Guardian, Ms Symonds could be heard screaming and telling the 55-year-old to “get off me” and “get out of my flat”.

Mr Johnson refused to comment on the incident during the leadership contest, despite repeated questions from journalists.