Kendal Nutricare is a Cumbrian firm with royal approval – as its products are regularly sent to Kensington Palace.

Prince Louis – fifth in line to the throne – is sent batches of the Mint Bridge Road plant's Kendamil Stage 2 formula and creamy oat porridge to enjoy.

The eight-month-old is the third child of William and Catherine, the Duke and Duchess of Cambridge and was born last April.

He is among thousands of customers across the world for the firm, which employs 138 people.

Kendal Nutricare chief executive Ross McMahon said the royal appointment began after he met Prince Charles at the Commonwealth Heads of Government meeting in April and talked to him about the company and invited him to visit the factory.

Kendal Nutricare also sent samples of Kendamil to Bath's Norland College, which trains the royal nannies.

Mr McMahon was then contacted by Maria Teresa Turrion Borrallo – nanny to Prince Louis and his siblings Prince George and Princess Charlotte.

He said: “She asked me questions for about an hour about the provenance of the product and the difference between Kendamil and other products.

“We sent our product to Norland for them to consider and taste test and they were very happy.”

Kendamil said it was the only infant formula made in Great Britain and Mr McMahon said displaying the Union Flag and the Red Tractor mark highlighted Kendamil’s provenance – with milk sourced locally from Cumbria and Lancashire farms.