Animal rights protesters have attacked a portrait of King Charles, which has been on show in a London art gallery.
Two protesters had stuck posters on the glass over the painting.
The Philip Mould gallery said that no damage had been done to the portrait.
The painting by Jonathan Yeo was the first official painting of the King since his coronation.
The Animal Rising group said that two of its supporters had attacked the painting in a way that they claimed was “light-hearted”.
They pasted over the royal portrait with a picture of Wallace, a character from the Wallace and Gromit animations.
They were criticising the welfare standards of RSPCA “assured farm” status, with King Charles a patron of the RSPCA.
“With King Charles being such a big fan of Wallace and Gromit, we couldn’t think of a better way to draw his attention,” said Daniel Juniper, one of those involved.
The group said its posters had been attached by water to the glass over the painting.
The gallery said the incident had been over quickly and no harm had been done to the artwork.
The painting, with its strong red colours, drew much public attention when it was unveiled by King Charles in Buckingham Palace last month.
The RSPCA said that it was “shocked by this vandalism” and that the attack on the painting was a distraction from its work helping animals.
“We remain confident that our RSPCA Assured scheme is the best way to help farmed animals right now, while campaigning to change their lives in the future,” said a spokeswoman for the RSPCA.