Charlotte in the picture on her first day at nursery school

The two-year-old, who is fourth in line to the throne, was photographed at Kensington Palace before travelling to nearby Willcocks Nursery School.

Charlotte is pictured sitting down on some outside steps in the grounds of the famous palace and another standing as she holds onto a rail.

The young princess is wearing a scarf, coat and appears to have a rucksack on her back as she is photographed by her mother.

The princess will be a full-time pupil at the nursery, which charges fees of just over £3,000 a term for pupils attending its Monday to Friday morning school, and employs lots of play as children learn.

Charlotte gives her mother a cheeky grin in the two pictures taken during Monday morning before she travelled to school for the first time.

Kate, who celebrates her 36th birthday on Tuesday, is a keen and accomplished amateur photographer who last year accepted a lifetime honorary membership of the Royal Photographic Society which recognised her "talent and enthusiasm".

The Duchess bucked tradition when she took the official photographs of her newborn daughter in 2015.

The photos of Charlotte showed the young princess being cradled by her older brother Prince George at William and Kate's Norfolk home, Anmer Hall.

The 35-year-old, a history of art graduate, has also released pictures to mark other milestones in her children's lives, including George's first day at nursery school and Charlotte's first birthday.

Charlotte was probably greeted by something familiar on her first day - her favourite toys.

Willcocks makes the gesture for all new children to help them make a smooth transition from home to school.

The school has been described in reports as having a loyal following of "old English families and chic foreigners'' and is something of a "hidden gem" in the shadow of the Royal Albert Hall.

It is likely Kate was invited into the nursery for her first "stay and play'' session with Charlotte, where the parent gradually spends more time away from their child until they are happy to be apart from their mother or father for the whole day.

Willcocks' website features glowing reviews from parents with one, only identified as Nikoleta, writing in July 2015: ''Alexander the Great once said about his teacher Aristotle: 'I owe my life to my parents, but I owe my good life to my teacher.'

''This statement certainly applies to all the teachers at the Willcocks Nursery School. A big thank you to all of you for everything you offered to Alexandra and for creating happy precious memories that will be part of who she is for the rest of her life.''

The nursery also received positive praise from Ofsted when it was inspected in 2012 and was rated outstanding.

The school charges fees of £3,050 per term for children attending what it calls morning school and £1,800 per term for those enrolled for the afternoon.

The choice for Charlotte is in contrast to the nursery picked for brother George, who was sent to Westacre Montessori School near the Cambridges' home in Norfolk. He is now a pupil at Thomas's Battersea.