The Queen has declined an invitation to visit youngsters at a village school, but she has thanked them for designing a range of knickers for her – including ones to wear while building sandcastles at Sandringham.

Pupils at Redbourn Infant and Nursery School, Long Cutt, wrote to the monarch after reading Nicholas Allan’s book “The Queen’s Knickers” and visiting Windsor Castle, where they noticed the Royal Standard flag flying, indicating the Queen was in residence.

The picture book, described as “naughty and charming” by reviewers, was republished to coincide with the Queen’s Diamond Jubilee.

Based on the monarch’s knicker closet and the many events she has to attend, a little girl wonders what underwear the Queen will choose to wear on a school visit.

Possibilities include her “at home” ones adorned with corgis, or woolly Balmoral ones.

Inspired by the book and castle visit, the Redbourn pupils decided to design some new knickers for the Queen.

Some were beach-themed while another pair had stars which play music “so you can dance”.

There was even special underwear for the evening, which plays lullabies “to help you go to sleep”.

To the infants’ surprise, the Queen’s Lady-in-Waiting responded to the letter.

Beneath the Buckingham Palace letterhead she wrote: “Her Majesty was interested to hear about the book you have been reading and to see the special designs which you have made.

“The Queen thought it most kind of you to take such care with your designs and to invite her to visit your school. Although Her Majesty is unable to accept, The Queen greatly appreciated your thoughtfulness.”