The Sun has become the first British newspaper to publish naked pictures of Prince Harry.

The tabloid argued the move was in the public interest and a "crucial" test of Britain's free press.

The photos of the prince frolicking in the nude with an unnamed woman in Las Vegas made headlines around the world but until now, no papers in the UK had used them following a request from St James's Palace, made via the press watchdog, to respect Harry's privacy.

The Sun said it was carrying the pictures in Friday's edition so the millions of people who get their news in print or have no internet access could "take a full part in that national conversation".

The story carries the headline: "Heir it is!" with an editorial explaining the reasons behind the newspaper's decision to print the photographs.

St James' Palace said it was down to the editors of Britain's newspapers to decide whether they printed the controversial pictures.

A palace spokesman added: "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."

Sun managing editor David Dinsmore said the paper had "thought long and hard" about whether to use the pictures and said it was an issue of freedom of the press rather than because it was moralising about Harry's actions.

He said: "The Sun is a responsible paper and it works closely with the royal family. We take heed of their wishes.

"We're also big fans of Prince Harry, he does a huge amount of work for this country and for the military and for the image of both of those institutions.

"We are not against him letting his hair down once in a while. For us this is about the freedom of the press.

"This is about our readers getting involved in discussion with the man who's third in line to the throne, it's as simple as that."