Police have been asked to look at claims that at least one worker attempted to access the confidential medical records of Catherine, Princess of Wales during her hospitalisation for abdominal surgery, a minister said on Wednesday.

The request follows a report in the Daily Mirror newspaper which said at least one attempt was made to access the private information at The London Clinic, a private hospital in central London.

Catherine, who is widely known as Kate and whose husband is heir to the throne Prince William, spent two weeks there in January.

Details of her condition have not been released but her Kensington Palace office previously said it was not cancer-related and that the princess wished her personal medical information to remain private.

Health minister Maria Caulfield said the rules on accessing patient information were "very, very clear".

"Unless you're looking after that patient, or unless they've given you their consent, you should not be looking at patients' notes," she told LBC radio.

"My understanding is that police have been asked to look at it," she said.

A statement from London's Metropolitan Police said it was "not aware of any referral... at this time".

Data 'breach' reported

The UK's data protection watchdog meanwhile said it would examine the matter.

"We can confirm that we have received a breach report and are assessing the information provided," a spokesperson for the Information Commissioner's Office (ICO) said late on Tuesday.

In a statement to the Mirror, The London Clinic said: "We firmly believe that all our patients, no matter their status, deserve total privacy and confidentiality regarding their medical information."

Kate was at the centre of controversy last week after she admitted editing an official portrait of her and her three children that was released by Buckingham Palace on Mothering Sunday.

It further stoked online speculation about her health and whereabouts after she had not been seen at a public event since a Christmas Day church service.

The palace had said in January she would require a lengthy recuperation and would not return to royal duties until at least April.

But instead of calming fears over her health, the edited picture sent the rumour mill into overdrive as media scrambled to pull the picture.

Catherine apologised but faced criticism even from usually supportive media.

British media have said that Catherine is still not due to return to public duties until mid-April.