Whoever said a picture was worth a thousand words would probably be amazed that a photo could be worth millions of dollars.

The scramble for the first official picture of Brad Pitt and Angelina Jolie's newborn daughter sparked a bidding war between some of the world's biggest media outlets and ended with People magazine reportedly paying more than $4 million US to secure the American rights to the first images of Shiloh Nouvel.

Meanwhile, celebrity magazine Hello!, which secured the British rights to the images, launched legal action with People Wednesday against two websites that printed a leaked exclusive shot of the couple with their new baby daughter.

But Hello! features editor Juliet Herd wouldn't comment on the amount the magazine paid for the rights but she did tell CTV's Canada AM the sum was "substantial."

"There's been so much interest in the photographs and the story of this baby and she's certainly the world's most famous baby and she's not even two weeks old yet," Herd said from London.

The leaked photo, which contains Hello! magazine's logo, shows a headline which reads: "The biggest exclusive of the year. Angelina and Brad with their new Baby Shiloh Nouvel."

The image, which shows Jolie lying beside the sleeping baby while Pitt looks on from the side, first surfaced on U.S. gossip blogs 'Oh No They Didn't' and 'Defamer' on Wednesday.

The photo "has been obtained totally illegally," Herd told Reuters.

"We were very shocked and horrified to see that this embargo has been breached."

Hello! and People are now "taking legal action around the world to stop Internet sites and everyone else who may seek to publish," Herd said.

Hello!, which sells in Britain, Spain, Turkey, Russia, Dubai, Thailand and Greece, says it has yet to discover the source of the leak.

"It's a complete mystery," added Herd. "And we are very concerned at this breach of copyright".

Meanwhile, a spokesperson for People magazine told reporters that "somebody from Hello! must have leaked it," a claim Hello! refutes.

Several websites have already removed the picture, but celebrity site Gawker.com insisted on keeping the image, claiming it was "fair use" to do so.

"We're firm in our right to report on Hello!'s treatment of the story, one of the biggest celebrity media news stories of the year," Gawker states on its website.

Veil of secrecy

Baby Shiloh Nouvel Jolie-Pitt was born on May 27 in Namibia, Africa, under a veil of secrecy.

Jolie, 30, gave birth at a private clinic in Walvis Bay. Delivered by Caesarean section, the baby weighed seven pounds and was said to be in good health.

Jolie and Pitt, 42, announced on Monday that they had agreed to let photo agency Getty Images market pictures of their newborn with all proceeds going to an as yet unnamed charity.

"The photos were sent to our offices in New York and London, and customers were invited in to view the photos on site and make decisions about whether they wished to bid for them," Jonathan Klein, Getty's CEO, told ABC News.

The images will be published by Hello! on Thursday, with People following on Friday.

Experts estimate that global rights to the pictures will have raised as much as $7 million US.

Celebrity photos

Celebrity photos, whether of babies or weddings, have generated huge price tags in recent years.

Catherine Zeta-Jones and Michael Douglas sold their first wedding pictures for more than $1.6 million US.

The first photo of Britney Spears' baby generated $500,000 US. The proceeds were given to a Hurricane Katrina charity.

And in 2005, Julia Roberts and her photographer husband, Danny Moder, sold a family photo to People for a reported $150,000 US. The money was donated to an environmental group.

The most profitable paparazzi photos to date are of Princess Diana and Dodi Fayed romping on a yacht, 10 days before the couple died.

Those photos reportedly made at least $500,000 US.