More than 850 people have complained about the Sun's decision to print photographs of Prince Harry naked, the Press Complaints Commission has said.
The PCC confirmed all complaints had come from members of the public, and none from St James's Palace.
On Friday, the Sun became the first UK newspaper to publish the images of the naked prince, taken in Las Vegas.
It said it was acting in the public interest as the images raised concerns about Prince Harry's security.
The paper also said the freedom of the press was being tested.
St James's Palace had contacted the PCC on Wednesday because it said it had concerns about the 27-year-old prince's privacy being intruded upon, in breach of the editors' code of practice.
The PCC said nearly all the complaints it had received over the matter related to invasion of privacy, and would be investigated in due course.
The pictures emerged from a private weekend the prince spent with friends. The two photos of the prince and a naked woman in a hotel room are believed to have been taken on a camera phone on 17 August.
They first appeared on US website TMZ earlier this week, which reported that he had been in a group playing "strip billiards".
In Friday's Sun, under the headline "Heir it is", the paper says: "Pic of naked Harry you've already seen on the internet."
Sun managing editor David Dinsmore said it would have been "perverse" not to publish the pictures, which "are now in the public domain in every country in the world".
Mr Dinsmore said the paper had thought "long and hard" about publication of the images.
He added: "Hundreds of millions of people have seen these pictures over the internet and it seems perverse that they shouldn't be shown in the pages of our newspaper.
"There is a public interest defence and part of that public interest defence is that if this thing has got so much publicity elsewhere that it would be perverse not to do it then that is acceptable and there is PCC case law on that basis."
But Paul Ashford, editorial director of the Daily Star and Daily Express newspapers, said "a very much stronger public interest ground" was needed to publish the pictures.
He said: "Once you know the story, once you know what good old Prince Harry has done, then - really - is there anything added in terms of public interest by actually seeing the pictures which everyone who wanted to see them had seen anyway?"
The Daily Mirror and the Independent said they had not published the photos because they considered that they breached the prince's privacy.
And Commons Culture, Media and Sport Select Committee chairman John Whittingdale said of the Sun's decision to publish the pictures: "The fact that [the photos] happened is well known. How the public interest is served by doing this is not clear."
A palace spokesman said: "We have made our views on Prince Harry's privacy known. Newspapers regulate themselves, so the publication of the photographs is ultimately a decision for editors to make."
The decision by British newspapers not to publish the pictures despite their publication elsewhere had prompted a debate about the impact the Leveson Inquiry was having on press behaviour.
The inquiry was set up to investigate the practices and ethics of the press following the phone-hacking scandal.
Conservative MP Louise Mensch, who is a member of the Commons Culture, Media and Sport Committee, said: "The Press Complaints Commission totally overstepped their bounds by going to the UK press en bloc and telling them not to publish these photographs.
"More to the point we cannot have a situation where our press as a bloc is so scared of the Leveson Inquiry that they refuse to print things that are in the public interest."
Meanwhile, a spokesman for the Metropolitan Police said none of the prince's police protection officers were facing disciplinary action after criticism in some press reports over their lack of intervention at the hotel room, adding that "as you would expect, senior officers have been briefed about the situation".