Prince George and the paparazzi

"There were lots of other tourists surrounding them," noted Hello! magazine in its cover story this week, "but the Duchess and her little boy escaped their attention."

Whether the passengers who shared a long flight with the Duchess of Cambridge, Prince George and their bodyguards really failed to notice their famous fellow travellers, or were simply decent enough to give the young mother some space, the celebrity title took a different view of her privacy.

"World Exclusive!" it trumpeted, as it laid out a sequence of a dozen paparazzi images showing the Duchess coming down the steps of the Boeing 777, babe in arms, and walking across the airport on the Caribbean island of St Vincent. The 10 pages of coverage, charting nothing more newsworthy than a transit to a private jet that would take the Royals to the island of Mustique, were accompanied by a breathless report recording every detail that could be gleaned from the pictures, down to Kate's "taupe Mint Velvet plimsolls". The Duchess, readers were informed, was wearing sunglasses "to shade her eyes from the hot tropical sun".

All of this must have made frustrating reading on the picture desks of some of Britain's national newspapers, which have been exceedingly careful not to intrude on the privacy of the Cambridges in the wake of Lord Justice Leveson's long inquiry into press standards. Here were Kate and George being pictured –without permission – from numerous angles across the airport and without complaint from the palace.

To cut its losses, the Daily Mail made a deal to print the cover of Hello! for a page seven article, while The Daily Telegraph published a news story containing the suggestion that the Duchess was more concerned with "image control" rather than protecting her privacy. It used the story as an excuse for running a huge, front-page picture of Kate and George, for which the Duchess had previously posed at her parents' house.

Phil Hall, a publicist and former editor-in-chief of Hello!, said: "I can't believe that Hello! would publish without permission – even if it was just off-the-record guidance that they wouldn't take any action against them."

The deal for the photographs, taken by an unnamed paparazzo, was brokered by Max Cisotti of Xclusive Pix!, a picture agency set up in 1992 and specialising in shots of royals. He says that the magazine had spoken to the palace and "got the green light" for publication. "We also waited until she came back [from Mustique], so there was no security issue."

Cisotti says that there were no lawful grounds for the royals to object to publication of pictures taken from a public place of subjects in a public place. "We live in a democracy, don't we? The palace doesn't rule us in any way shape or form."

He agrees that since the Leveson Inquiry into press standards, newspapers have been "very, very cautious" about publishing paparazzi material.

Niri Shan , the head of intellectual property and media at lawyers Taylor Wessing, says: "The newspapers are self-censoring because they have the spectre of politicians coming in and trying to regulate them."

It helps explain why the shots were sold to a celebrity magazine famous for its approving treatment of the royals and other celebrities. "It's a favoured destination because once it's in Hello!, it's a bit more accepted and that makes it easier," explains Cisotti. "Usually Hello! manages to clear things because of its reputation."

When the magazine comes off the news-stand next Monday, he will hope to sell the images again to Fleet Street. But if a pap may look at a king, how much longer will newspapers be prepared to settle for seconds remains to be seen.