Six on trial over topless photos of Duchess of Cambridge
The Duke of Cambridge has said the publication of topless photographs of his wife in a French magazine was "all the more painful" given his mother's experience with the paparazzi.
A statement from the duke was read at the French trial of six people accused of invasion of privacy and complicity.
The images were taken as the royal couple holidayed in Provence in 2012.
They appeared in Closer magazine in France, while regional newspaper La Provence printed swimwear pictures.
Paris-based agency photographers Cyril Moreau and Dominique Jacovides are accused of taking long-lens shots of the royals, including the topless pictures of the Duchess of Cambridge, from a public road.
The others accused in the case, being heard at Nanterre, near Paris, are Closer's editor Laurence Pieau, Ernesto Mauri, chief executive of the Mondadori group which owns the magazine, La Provence photographer Valerie Suau, and Marc Auburtin, the paper's publishing director at the time.
A prosecutor urged the court to impose "very significant fines" while a lawyer for Prince William and Catherine called for "very large damages".
Paul-Albert Iweins, representing Closer magazine, said the duke and duchess were hoping to claim 1.5 million euros (£1.3m) in compensation.
He argued that the couple had been the subject of much media attention - including the broadcast of their wedding - and that the photos did not constitute a breach of privacy and cast them in a positive light.
'Enjoy our privacy'
The royal couple had been staying at a chateau in Provence owned by Viscount David Linley, the nephew of the Queen.
Prince William's written declaration was read out by the couple's lawyer Jean Veil.
He said: "My wife and I thought that we could go to France for a few days in a secluded villa owned by a member of my family, and thus enjoy our privacy.
"We know France and the French, and we know that they are, in principle, respectful of private life, including that of their guests."
He added: "The clandestine way in which these photographs were taken was particularly shocking to us as it breached our privacy."
He said the images were "all the more painful" given the experience of his mother, Diana, Princess of Wales, who died in a car crash in Paris in 1997 as she was being pursued by photographers.
The court heard mobile phone data had placed Mr Moreau, 32, and Mr Jacovides, 59, in the area between 4 and 6 September 2012, when the topless images are believed to have been taken.
Both men deny they were responsible for the pictures used by Closer.
Photographs of the duchess in her swimwear used in La Provence are said to have been taken by Ms Suau, 53, but she told the court there had been no intention to breach the royal couple's privacy.
The duke and duchess are not due to attend the court, which is expected to announce its verdict on 4 July.
In 2012 they launched legal proceedings and a court in Paris banned Closer, which is a separate publication from the UK's Closer magazine, from printing any further images.
St James's Palace issued a statement at the time describing the incident as being "reminiscent of the worst excesses of the press and paparazzi during the life of Diana, Princess of Wales".