Fabio's Gelato, based in Hitchin, Hertfordshire, only began making its Percy Pig ice cream last week.

But the retailing giant sent the owner Fabio Vincenti a letter which said he could continue to use the sweets, but not the name of the product.

"It is what it is, they've got to protect Percy Pig," he said.

Marks & Spencer said the name of Percy Pig, which started life as a bag of sweets in 1992 but has since evolved to other ranges, could only be used on "official M&S products".

Fabio Vincenti runs the ice cream parlours in Hitchin and Letchworth with his wife Hannah

The ice cream parlour uses several different branded items for flavours, including chocolate bars, energy drinks and Marmite.

Mr Vincenti said: "We've done so many different brands of ice cream."

He said the feedback was generally positive from the various companies but he "wondered why no-one ever moaned and always knew someone might say something".

The "polite and fair" letter from M&S was received on Thursday, along with some packets of the swine-faced treat, he said.

'Fabio's Pig'

Mr Vincenti posted a copy of the letter on social media, saying he could continue to make the ice cream, but had to change the name to something such as "Pig Faces or Pig Sweets".

The letter said: "Percy Pig is one of our 'hero' brands and we own trade marks to protect it.

"We risk losing those trade marks (and more importantly to us, consumers will no longer be confident Percy Pig-branded products originate from M&S) if we do not take steps to stop others from using them without our permission."

Mr Vincenti said the ice cream had already proved popular online and would, for now, be renamed "Fabio's Pig".

An M&S spokesman said it was "careful to only put [Percy Pig's] name on official M&S products".

"It's flattering that he's inspired Fabio's new gelato and we hope they enjoy the treat we sent," he said.