Prince William and his wife, Kate Middleton, are taking legal action against high-society magazine Tatler over a “cruel, sexist and woman-shaming” cover story about the duchess, according to a report.

The Duke and Duchess of Cambridge have already sent legal letters to the magazine demanding its profile of Kate be removed from the internet, the Mail on Sunday newspaper said.

The story, headlined “Catherine the Great” on the cover of the magazine’s latest issue, remained online Sunday.

While it starts out flattering — suggesting the duchess is now “one of the most influential women in the world” — Kensington Palace has already blasted it for a swathe of “inaccuracies and false representations.”

Insiders told the UK paper that the royal couple were particularly incensed at the suggestion the duchess was feeling exhausted and trapped by an increased workload after Megxit.

They were also infuriated at the “disgusting” line about her being “perilously thin,” comparing it to eating disorders suffered by William’s late mother, Princess Diana.

“That is such an extremely cruel and wounding barb,” a royal source told the UK paper.

“It’s sexist and woman-shaming at its very worst.”

The source insisted that the duke and duchess were only taking legal action because the article was “full of lies.”

“It’s ironic that the Royals’ favorite magazine is being trashed by them,” the source noted.

“Tatler may think it’s immune from action as it’s read by the Royals and on every coffee table in every smart home, but it makes no difference.”

After Kensington Palace released its unusual attack on the “inaccuracies and false misrepresentations,” Tatler’s Editor-in-Chief, Richard Dennen, insisted he “stands behind the reporting.”

Tatler did not respond to the Mail on Sunday on its latest report. Kensington Palace declined to comment, the paper said.