Prince Charles has long been keen to make cars eco-friendly – 10 years ago, he converted his old Aston Martin to wine-based fuel. Now he is planning to go one step further and introduce an electric car to his fleet, The Telegraph can reveal.

The Prince of Wales has test-driven a luxurious Tesla car on his Scottish estate – and in the process made an unlikely friend in Kimbal Musk, the cowboy hat-wearing younger brother of Tesla chief executive and Silicon Valley magnate Elon.

The Prince personally hosted Mr Musk, who sits on the board of Tesla, and his fiancée at Dumfries House in Ayrshire over several days in 2016 as part of the test drive of a black Tesla Model S. Mr Musk said the Prince shared his “frustration” at being seen as out of touch over his views on sustainable food, and “anger” that people have been “poking fun at him”.

The Prince’s office then engaged in discussions about securing the car. Clarence House made the initial approach to Tesla, asking for the test drive, and the discussions included plans for Tim Williams, the Prince’s head driver, to visit a Tesla showroom and select a car.

While the Prince later hosted the Tesla board member again at Clarence House, it is understood his fleet’s new electric additions are more likely to be provided by Jaguar Land Rover, which holds the royal warrant.

A spokesman for Clarence House said: “There is definitely a plan for us to incorporate electric cars into the royal fleet,” adding there are ongoing discussions with Jaguar Land Rover about how and when the cars could be included.

Daniel Shakhani, a social impact entrepreneur who has been involved in the Tesla discussions, said: “Bringing an electric car into the royal fleet would positively reflect the Prince’s commitment to his work on climate change.”

Mr Musk co-founded The Kitchen, a restaurant group focusing on farm-to-table food, and Big Green, a charity that builds learning gardens across America. He bonded with the Prince over their love of what he calls “real food”, which “you trust to nourish your body and the planet”.