The King was all smiles with David Beckham as he celebrated the work of his foundation alongside other celebrity ambassadors including Sir Rod Stewart and Naomi Campbell.

Charles attended the King’s Foundation inaugural awards ceremony which showcased the work of students, teachers, alumni and partners who have contributed to the organisation’s charitable efforts in London on Tuesday evening.

The foundation is the custodian of the Highgrove gardens and offers workshops, programmes and short courses focused on heritage and craft skills at its Barley Court education centre on the estate.

Animal Rising activist Dan Juniper said: “We know that King Charles is a big fan of Wallace and Gromit, [as] he has publicly said before.

“And so we wanted to get King Charles’s attention in a way that he would enjoy and therefore be more likely to listen to us.”

Gallery owner Philip Mould explained that it was behind a piece of glass that protected the image of the King when the Monarch’s face was replaced with that of the animated character Wallace and a speech bubble was added.

“We had anticipated that there might be these type of responses,” Mould said of the portrait, which hangs in London’s Philip Mould Gallery.

“(The painting) is safely secured in its frame with protective layers.

“One always lives with that thought these days. I wasn’t hugely surprised.

“The attack on the picture was not actually of a serious nature. The perpetrators put water on the surface very quickly in a swift manoeuvre and then they added stickers to that.

“No damage was done. The stickers only remained up for about 10 or 15 seconds, and then were taken down by my gallery staff.

“I asked the individuals to leave and they did.”