Britain's royal family on Saturday condemned the 'greed' of an Irish newspaper that published topless photographs of Prince William's wife Catherine, and warned an Italian magazine not to follow suit.

The grainy images of Catherine sunbathing in her bikini bottoms appeared in Saturday's Irish Daily Star, a fresh blow to the royals a day after they launched legal action against the French magazine that first printed them.

"There can be no motivation for this action other than greed," said a spokeswoman for Catherine and her husband, the second-in-line to the British throne.

The two media groups that jointly own the Irish Daily Star also condemned the decision to run the shots, which were taken with a long lens while the couple, both 30, were holidaying at a private chateau in the south of France.

Britain's Northern and Shell group said it was taking "immediate steps" to shut down the joint venture with Dublin-based publisher Independent News and Media which operates the Irish Daily Star.

"The decision to publish these pictures has no justification whatever and Northern and Shell condemns it in the strongest possible terms," said the company's chairman Richard Desmond.

Independent News and Media said it had no prior knowledge of the decision, which it described as "regrettable and in poor taste".

The Irish Daily Star's editor Mike O'Kane admitted that he was running the pictures to sell more papers, and said he had treated Catherine as he would any other celebrity.

"The duchess would be no different to any other celeb pics we would get in, for example Rihanna or Lady Gaga," he told the BBC.

"She's not the future queen of Ireland so really the only place this is causing fury seems to be in the UK."

The photos would not appear in the British or Northern Irish editions of the Daily Star, he added.

The royal family also warned Italian gossip magazine Chi on Saturday that "unjustifiable upset" would be heaped upon Catherine if it went ahead with plans to print the photos.

Apparently undeterred by the launch of legal action against French magazine Closer, which first ran the pictures, Chi said on Friday that it would print 26 pages of them in a special edition on Monday.

The magazine's editor Alfonso Signorini said the pictures were "a scoop" he could not afford to miss.

"If I wasn't capable of recognising the true value of a scoop I would do better to go and sell artichokes at the market," he told the ANSA news agency.

Both Chi and Closer are part of the media empire of former Italian prime minister Silvio Berlusconi.

A palace spokeswoman declined to comment on whether the royal family was launching legal action against either Chi or the Irish Daily Star.

"All proportionate responses will be kept under review," she said.

Closer magazine confirmed to AFP that there would be a hearing on the complaint on Monday at a court in Nanterre, north-west Paris.

William and Catherine, who are currently in Malaysia as part of a tour to mark Queen Elizabeth II's sixtieth year on the throne, put on a brave face for the cameras on Saturday during a visit to a Borneo jungle.

The prince is said to be furious over the images, which drew comparisons with press harassment of his mother Diana who died in a Paris car crash in 1997 pursued by paparazzi.

He is believed to blame the press photographers for his mother's death.

In a strongly worded statement on Friday, palace officials said the pictures were a "grotesque" breach of privacy.

"The incident is reminiscent of the worst excesses of the press and paparazzi during the life of Diana, Princess of Wales, and all the more upsetting to The Duke and Duchess for being so," they said.

Closer has insisted it has no regrets about printing the pictures.

This is the second furore over scantily-clad British royals in a month, after nude pictures of William's brother Harry, frolicking with a mystery woman in a Las Vegas hotel suite, went viral on the Internet.