Tesco and P&G are locked in a bitter dispute over the sale of Eukanuba petfood.
P&G has told the retailer to stop selling the brand, which it says is designed for sale through petshops and vets' surgeries only.
It claims Tesco is sourcing the range through grey channels on the Continent and is selling it through 23 stores without its approval.
"P&G remains committed to exclusively supporting Eukanuba in the pet speciality channel, where owners can get information about the nutrition and health benefits of these premium products to guide their choice," a spokeswoman said.
Eukanuba was designed to provide the exact nutritional requirements for different sizes, ages and breeds of cats and dogs, she added.
Tesco staff would not be qualified to correctly advise pet owners on the correct selection to provide optimal nutrition, she claimed.
Tesco, which declined to comment, has not broken any laws.
Under EU trademark rules, a company can import branded goods from another member state and sell them without the manufacturer's agreement.
But the Eukanuba incident has echoes of last September's dispute between Tesco and Tyrrells.
The crisps manufacturer scored a publicity coup when Tesco agreed to delist its products - on Tyrrells' request.
P&G also manufactures the Iams petfood brand, which is widely available through supermarkets.