A bitter fast food war has erupted in Italy after a McDonalds' advert, which claimed Italian children preferred happy meals to pizza, caused so much offence chefs are now threatening legal action. Restaurateurs in the country are so angry with the US corporation, the largest chain of burger restaurants in the world, for attacking their cultural diet that have said they will take them to court. The row erupted over an 18 second video advert advert which appeared to prove that kids preferred a Happy Meal to a margherita pizza. Scroll down for video . The advert has Italian chefs in uproar, as it appears to claim that Italian children prefer happy meals to traditional pizza . The advert opens in a traditional Italian restaurant where the young Italian boy appears bored by the pizzas . A top pizza chef described the advert 'blasphemy' and the True Neapolitan Pizza Association has accused McDonald's of a 'shameful' attack. The McDonald's spot shows a waiter in a traditional pizza restaurant asking a small boy, who is peering at a menu with his parents, which pizza he would like. He replies he wants 'A Happy Meal', and the camera then pans to a shot of the family sitting in a McDonald's with his meal. At the end of the advert a voice says: 'Your little boy had no doubt.' Massimo Di Porzio, vice president of The True Neapolitan Pizza Association in Naples, said: 'We've had enough of them making money at the expense of children's health. 'Our legal team is looking at the possibility of legal action to put an end to this shameful attack on a symbol of the Mediterranean diet. 'It is not the first time and it will not be the last time McDonald's has tried to attack our cultural traditions but this time we are intent on taking action, which, if we win, will allow us to invest in courses to help educate children about food.' Eduardo Pagnani, owner of the famous Pizzeria Brandi in Naples, said it was 'blasphemy' to suggest children preferred hamburger . Riot police had to protect McDonald's branches in 20 Italian cities when demonstrators flung raw meat at stores in 2000 . Eduardo Pagnani, owner of the famous Pizzeria Brandi in Naples, said it was 'blasphemy' to suggest children preferred hamburgers. He stormed :'Don't ridicule pizza, it is quality food and the best known in the world,' McDonald's claimed that probably all the great chefs in Naples had brought their children to the restaurant chain and they had not meant to attack Italian food culture. It is not the first time McDonald's and Italian foodies been at odds over their menus. Riot police had to protect McDonald's branches in 20 Italian cities when demonstrators flung raw meat at stores in protest at the growth of massive food companies in 2000. In 1986 a huge demonstration against the location of a new restaurant at the Spanish Steps in Rome led to the formation of the world famous Slow Food movement. Even the waiter, whose Italian restaurant is slammed in the ad, appears delighted with the child's choice .
Italian chefs threaten legal action against McDonald's over new kid's advert.
The 18 second video claims country's children prefer Happy Meals to pizza.
One top Italian chef calls the advert 'blasphemy' and McDonald's shameful.
The advert is latest in a long-running feud with Italian foodies and the chain.