SKY News is reporting that press photo agencies, including Reuters, Associated Press and Agence France-Presse, have pulled a new image of the Princess of Wales from circulation over concerns that it has been “manipulated”.

The Associated Press (AP) has told Sky News the photo shows an “inconsistency in the alignment of Princess Charlotte’s left hand”.

The picture in question was released on Sunday morning to celebrate Mother’s Day and shows Kate surrounded by her and Prince William’s three children: Prince George, Princess Charlotte and Prince Louis.

The image was initially circulated by a number of picture agencies but on Sunday night at least three withdrew it and told media outlets to “kill” the photo from their systems and archives.

AP told Sky News in a statement: “The Associated Press initially published the photo, which was issued by Kensington Palace. The AP later retracted the image because at closer inspection, it appears that the source had manipulated the image in a way that did not meet AP’s photo standards.

“The photo shows an inconsistency in the alignment of Princess Charlotte’s left hand.”

The editing of photographs after they have been taken for professional purposes is a common practice, and there is no suggestion Kensington Palace was trying to do anything other than improve the photo if it has been altered.

Kensington Palace has declined to comment after the photo was pulled by picture agencies.

In a message accompanying the photo on Instagram, Kate wrote: “Thank you for your kind wishes and continued support over the last two months.

“Wishing everyone a Happy Mother’s Day.”

The Prince and Princess of Wales’s Instagram post featuring the image has not been taken down.

The picture and message came amid speculation about Kate’s health following a brief hospital stay in January.

Kate was admitted for planned abdominal surgery on 16 January, exactly a week after her 42nd birthday.

The following day, the Palace said the operation was successful and Kate stayed in hospital until 29 January, when she was discharged home to Windsor.

At the time, Sky News understood that her recuperation would likely take between two and three months.

Kate has not been seen in public since she joined other members of the Royal Family for a Christmas Day walk, though US celebrity news site TMZ published a photo of her on 4 March.

The photo was understood to have been taken by unauthorised paparazzi near Windsor Castle.

William has been attending events and engagements solo while Kate has been recuperating.

UPDATE: Today (Monday) Kate Middleton has broken her silence on the row surrounding a photo issued by the royal family on Mother’s Day.

The Princess of Wales has personally apologised for confusion over the family photograph issued by Kensington Palace saying: “Like many amateur photographers, I do occasionally experiment with editing.”

She added: “I wanted to express my apologies for any confusion the family photograph we shared yesterday caused. I hope everyone celebrating had a very happy Mother’s Day.”

• Not many pictures which have not been altered in some way appear in newspapers and press websites. Photo-shopping, cropping and other means of altering pictures are all in daily use by picture desks. Why the outcry over this one picture? It is quite legitimate for The Princess of Wales to have chosen this particular picture. She could have personal reasons which could include that she felt she was not looking her best after her time in hospital. If a newspaper asked for a picture of you for publication wouldn’t you give them one in which you believed you looked your best? This story could be much ado about nothing. Newspapers can take pictures of anyone without their permission provided this happens in a public place. Let’s hope that she enjoyed Mother’s Day. That she is looking well and that we will see her back on duty soon looking fit and well. Editor, The Democrat