Fast food chain McDonald's has hit back at criticism by Prince Charles after he appeared to suggest banning its food was the "key" to improving diet and fitness.

The Prince was touring a diabetes centre in Abu Dhabi, in the United Arab Emirates and was told about initiatives to improve the nation's diet and fitness.

He asked nutritionist Nadine Tayara from the centre: "Have you got anywhere with McDonald's? Have you tried getting it banned? That's the key."

A spokeswoman for McDonald's said Charles's remark was "disappointing" and added: "This appears to be an off-the-cuff remark, in our opinion.

"It does not reflect our menu or where we are as a business."

She said Charles was clearly unaware of some of the moves the company has made, including improved labelling, supporting sustainable agriculture and nutritional changes with choice and variety.

The Prince, who visited the centre with the Duchess of Cornwall as part of their 10-day tour of the Gulf, is a keen advocate of organic food and in 1986 set up a farm on his Highgrove Estate that does not use artificial pesticides or fertilisers.

However, it was reported today that his celebrated Duchy Originals range of foods contains products with higher calories, fats and salt than in a Big Mac.

In August 2005, Prince Harry was reportedly spotted tucking into a McDonald's "buy one get one free" chicken burger meal in Plymstock, Devon.

The British Medical Association has raised general concerns about "junk food".

The BMA said there are around one million obese children under the age of 16 in the UK.

Penny Mordaunt, of Diabetes UK, said: "Good education about the damage a diet high in sugar, fat and salt can do is the best way to encourage people to change their eating habits."

Josh Bayly, of the British Heart Foundation, said that tackling Britain's "junk food culture" was the key to the future health of our children.