Naked chef Jamie Oliver is taking his healthy eating crusade across the Atlantic to confront what he calls the "most unhealthy country in the world".

Speaking in New York, Mr Oliver told Reuters that as an "English boy in America, they might not appreciate my honesty" but claimed American politicians are "subservient" to "junk food companies".

In the Big Apple to promote the launch of his new book and TV series on Italian cooking, Mr Oliver added that "a fat person in England isn't the same as a fat person in America", and urged the US to follow the example set by the UK to ban food items such as Turkey Twizzlers from school dining halls.

However, he did back the moves made by New York mayor Michael Bloomberg to ban trans-fats in almost all of the city's restaurants.

"The junk food companies have got more resources than the government and more money to spend on poxy lawyers so I completely admire ... the mayor for doing it," he said.

The ban by Mr Bloomberg is in part credited in influencing the recent decision of KFC to remove all trans-fats from its products.