Kate Middleton, girlfriend of Britain's Prince William, has filed a formal complaint to the Press Complaints Commission (PCC) about a photograph of her that appeared in today's Daily Mirrornewspaper.
The picture, which appeared on page 22, shows her glancing over her shoulder as she walks along the street holding a coffee and was accompanied by a caption suggesting "stony-faced Kate" was about to scold William after he was pictured this month with other women in night clubs.
"Look out Wills, here comes an heir-bashing" ran the headline.
Ms Middleton's complaint said the unsigned photograph was taken as a result of harassment, a PCC spokesman said, adding the commission would investigate.
Former Daily Mirroreditor Roy Greenslade said Ms Middleton might have taken offence at the caption, which seemed to imply that the writer knew what she was thinking, rather than the picture itself.
"What doesn't help is that the caption accompanying it is one of those pieces of rather speculative whimsy, in which the writer is pretending that he knows what she might be thinking," Mr Greenslade told Sky News.
"I think that's doubly offensive."
William, elder son of heir to the throne Prince Charles, and Ms Middleton, both (24), met when they were students at St Andrews University in Scotland.
Police protection for Ms Middleton has been stepped up as paparazzi relentlessly pursue her in the same way they did William's mother, Princess Diana.
Images of her already attract thousands of pounds and with media speculation rife that William is set to propose, photographers are following every move of Britain's possible future queen.
Lawyers for Ms Middleton had previously written to newspaper editors urging restraint and warning that one possible avenue was to complain to the PCC.