Image copyright Matt Porteus/PA Image caption The Duke and Duchess of Cambridge have released pictures of Prince George at various milestones in his life

Photographs showing Prince George sitting on a police motorbike have been ruled to be a breach of privacy by the press standards watchdog.

The Duchess of Cambridge complained after the images were published online by the Express and OK! magazine in May.

Prince George was seen through the railings of Kensington Palace along with the Duchess and four officers.

The Independent Press Standards Organisation (Ipso) said it was a "private activity on private land".

The pictures show the Duchess smiling as the young prince, aged three, reaches out for the motorbike's handlebars.

The officers, believed to be motorbike outriders, look on while one is showing him the controls.

Ipso's complaints committee said the photographs had been taken when the royals had "a reasonable expectation of privacy".

'No public interest'

"They were engaged in a private activity; the images had been taken while they were on private, protected land where commercial photography is prohibited; and no permission for the images to be taken or published had been sought or obtained," it said.

The committee added that both the news website and magazine "denied that the images had shown the complainants in a private interaction".

They said the police officers were photographed while on duty, and they "considered that it was important for the public to see how young members of the Royal Family interacted with public servants, particularly when the officers had been 'commandeered for a three-year-old's entertainment.'"

Image copyright CHRIS JELF Image caption The royals have previously warned the press about intruding on their children's privacy

Ipso said it agreed they were public figures but no public interest had been served with images which "simply showed Prince George playing on a police motorbike".

"They were photographed standing within the grounds of their private home, in a position that was not easily visible to the photographer; they were not carrying out any official duties, and they were unaware they were being photographed," it said.

The Duke and Duchess of Cambridge have released family photographs of themselves and their two children at various milestones in their life.

Kensington Palace has also released several warnings about press intrusion including after the birth of their daughter Charlotte.