The Duke and Duchess of Cambridge are to launch a photography competition.

The couple's charitable organisation, the Royal Foundation, have applied tot he Intellectual Property Office to trademark the Earthshot Prize.

According to the Daily Mail newspaper columnist Sebastian Shakespeare, the application suggested the name could be used for photographs, clothing, footwear and headgear.

The paperwork also covers education and training services, publishing and cultural activities, and all relate to nature conservation and the environment.

A spokesperson for Kensington Palace declined to give any details of the prize.

Duchess Catherine herself is a keen photographer and official images of the couple's three children, Princes George and Louis, six and 17 months, and four-year-old Princess Charlotte, have typically been pictures she took herself.

The 37-year-old royal succeeded Queen Elizabeth as patron of the Royal Photographic Society earlier this year.

Meanwhile, last month the duchess made her Instagram debut after she and William paid a second visit to the SOS Children's Village in Lahore, Pakistan, after their Airbus A330 RAF Voyager jet was forced to make an emergency landing due to an electrical storm.

In a post on the Kensington Royal account, Catherine shared a series of photographs from the tour, including one of William holding hands with and hugging two young boys at the National Cricket Academy and another of his wife having a giggle with a group of girls.

Catherine's message read: ''The community at the SOS Village is built around family - and the best possible family you could imagine - where everyone comes together to nurture, love and protect the children in their care.

''These vulnerable children, many who have come through traumatic circumstances, are nurtured in this caring environment and are able to form these quality relationships that they so desperately need to thrive. - Catherine.''