Carrie Symonds put a loving arm around her boyfriend Boris Johnson last night as they were seen entering Downing Street together for the first time.
The Prime Minister's 31-year-old partner was beaming at him as they arrived at No 10 at just before midnight to spend their first night there as a couple.
Carrie, who was wearing a red and green polka-dot summer dress, had been ushered into a silver Jaguar by two bodyguards at around 8pm before being swept out of Downing Street to meet the Tory leader.
But the first unmarried couple to officially live in No 10 arrived back home together around four hours later, probably after dinner and drinks in central London.
Carrie Symonds puts her arm around Boris Johnson as they arrive at Downing Street to spend their first night there as a couple
The former Tory communications chief smiled broadly at the Prime Minister as they entered No 10 at midnight last night
Carrie and Boris were grinning as they start their new life together behind the world's most famous black door
The unmarried couple are shown in the centre of the picture entering the back door of No 10 followed by two of the PM's bodyguards
Carrie was flanked by security as she got into a silver Jaguar and went out to meet the PM at around 8pm
They have chosen the larger four-bedroom flat at No 11 Downing Street instead of the smaller official residence at No 10, which is being taken by new Chancellor Sajid Javid.
Boris separated from his second wife Marina in September after he was thrown out of the family home and he is widely expected to propose to Carrie once his divorce is finalised later this year.
Mr Johnson and Mr Symonds had been living together at her flat in Camberwell, south London, until a well-publicised plate-smashing row recorded by neighbours who claimed she yelled 'get off me' and 'get out of my flat'.
In public Carrie has kept her distance from the PM, not attending the ceremony where he was elected was Tory members and she stood at the end of Downing Street watching him as he gave his first speech outside No 10.
Carrie was seen leaving Downing Street by a back entrance today
Carrie climbs into the Government Jaguar at the beginning of the evening out yesterday
The luxury car was then swept out of Downing Street's smaller entrance, close to Horseguard's Parade and St James' Park
Four hours later 31-year-old Carrie was pictured smiling broadly at her boyfriend Boris
The former Tory communications chief, who left her job after her relationship with the now PM started, grabbed his arm after leaving the Jag
Her hand then moved to the middle of the Prime Minister's back and she gave him a rub
She then followed her partner into his official residence to spend their first night there together
But the couple were tactile and openly affectionate as they arrived, smiling, at the Prime Minister's central London home via its rear entrance late yesterday.
Deliveries from John Lewis were pictured arriving at No 10 yesterday - two days after the new Prime Minister officially moved in with Miss Symonds.
The prime minister moved in on Monday while Miss Symonds stayed there for the first time last night alone while he was in Northern Ireland meeting the leaders of the five political parties in Ulster.
A trolley full of parcels from John Lewis was pictured being carried through the front doors of No 10 this morning including what appeared to be glassware, according to markings on the cardboard boxes.
A spokesman for No 10 refused to comment on the delivery and why it was taken through the front door, adding it was a 'personal matter'.
Former PR executive Carrie was seen moving furniture into the four-bedroom home with her mother Josephine Mcaffee.
Carrie Symonds has moved No 10 with her boyfriend Boris Johnson
A large delivery was pictured arriving at the front door of No 10 Downing Street today just two days after new Prime Minister Boris Johnson moved in with partner Carrie Symonds
The couple have moved into the large four-bedroom flat above No. 11 rather than the official residence at No 10 and will furnish it 'at no additional cost to the taxpayer'. Boxes labelled John Lewis were seen being carried in today, suggesting the couple may be furnishing their new home
Mr Johnson's spokesman has confirmed they will furnish the flat with their own money and Miss Symonds will live there 'without any additional cost to the taxpayer'.
They have set themselves up in the spacious four-bedroom apartment previously lived in by ex-chancellor Philip Hammond and his family, who left last week.
The couple moved in on Monday and No. 10 confirmed Miss Symonds was living with him.
Miss Symonds, pictured in Westminster on Monday, will also live at the flat at no extra cost to the taxpayer, a No. 10 spokesman said
It is believed that Mr Johnson will be re-furnishing the flat out of his own pocket, with the deputy spokeswoman saying: 'There will not be any additional cost to the taxpayer.'
Last weekend the couple spent time at Chequers, the palatial grace-and-favour countryside retreat in Buckinghamshire.
Ms Symonds, a former Tory spin doctor, will not have any publicly-funded staff working for her, No 10 said.
The spokeswoman said: 'In relation to her living at No 10 there won't be any additional cost to the taxpayer.'
The four-bedroom apartment above the finance minister's office has been home to PMs and their families since 1997, when Tony and Cherie Blair chose it over the two-bedroom flat above the more famous black door.
But while the Blairs (like the Camerons) had a young family, Boris, whose children are grown up, will share the spacious living quarters with only Ms Symonds, 31.
Mr Johnson, pictured in Belfast yesterday where he was meeting Northern Irish officials before returning to London to see Carrie
Mr Javid by contrast has a wife and small children, who may struggle to squeeze into the two-bedroom apartment above his new HQ.
It is believed however that they will stay at the large family home in Fulham which features added security since he was made home secretary last year.
Earlier this month Mr Johnson and his partner bought a £1.3million Victorian semi-detached home in Camberwell, south London, not far from her previous flat.BoJo's abodes: How new Prime Minister Boris Johnson made it to the top of the property ladder via a hip New York apartment and a not-so-trendy Wolverhampton terrace!
Boris Johnson finally moved into Downing Street this week.
The domestic arrangements of our peripatetic PM have been complicated to say the least — booted out of his marital home and spending his time between girlfriend Carrie Symonds’s flat and houses lent by friends.
But wanderlust has been a regular feature of his life — since the age of 15, he has moved 32 times.
Here, David Wilkes maps the many homes of Boris . . .
First home: New York
Boris was born in June 1964 in Manhattan, where his father, Stanley, studied economics at Columbia University.
The family home was a loft apartment opposite artist Andy Warhol’s haunt, the funky Chelsea Hotel on West 23rd St.