Beloved by Hemingway, philosophers and impressionists alike, Paris’ bistros and cafe terraces are seeking UNESCO world heritage status as unique "intellectual and artistic melting pots”.

Bastions of Parisian art de vivre, bistros have also become symbols of defiance to the 2015 terror attacks on the French capital, which targeted their easy-going, open-minded spirit but failed to break it.

The atrocities carried out by Islamic State gunmen were the worst in France's history and left 130 people dead.

“(After the attacks) Parisians crowded onto the terraces... to show that they regarded them as places of cultural cross-fertilisation, of freedom and of the art of living,” said the group of bistro owners, backed by a string of French actors and aficionados.

The association has launched a campaign to raise awareness both in France and abroad of the role that “bistro and cafe terraces play in “bringing people and cultures together”.

They want the French ministry to back their candidacy to be awarded “protected” status and be added to the UNESCO intangible cultural heritage list alongside the likes of the French gastronomic meal.

They will hand in their request in to the ministry in September.

With their trademark zinc counters, bistros have been immortalised in countless films from Amelie to Woody Allen’s Midnight in Paris. The oldest in Paris, the 17th-century Procope, is still standing. They have also served as headquarters of painters and writers, such as Boris Vian, Jean-Paul Sartre and Simone de Beauvoir.

Indeed, the French capital only remains a “moveable feast”, as Ernest Hemingway put it, “because its bistros and cafes exist”, said the association.

Yet bistro culture is under threat, warned Alain Fontaine, the group’s head and owner of the Masturet bistro, near the city’s former stock exchange.

Paris now has less than 2,000 bistros among the capital’s 14,000 restaurants, meaning they have dropped from around 30 per cent 20 years ago to 14 per cent today, he said, citing soaring rents in Paris but also powerful food and drink chains.

“For the past ten years, the bistros and terraces of Paris have been losing ground to sandwich sellers, fast food joints and exotic restaurants, and they take with them an art de vivre, a sense of sharing and an ethnic, religious and social mix,” said Mr Fontaine.

Foreigners would lose out too, he said, because “tourists don’t only come to see the Eiffel Tower or the Louvre museum, they’re here to meet the people of Paris on our terraces,” he said.

One of the problems facing bistros were the long hours, from seven in the morning until 11pm often, meaning that family-run businesses are hard to keep going.

“Very few (children of owners) want to take on the bistro of their parents,” he said. “If we’re inscribed as UNESCO world heritage treasures, they’ll stay in our bistros, take them over, and save them."

However, competition for the coveted status is fierce in France, which can only field one proposal every two years.

Among high-profile candidates of late are the French baguette and Paris’ iconic booksellers, known as “bouquinistes”, whose green stalls line the river Seine and make up the world’s largest open-air bookshop.

The book vendors recently received tacit backing from the Paris town hall, but the culture ministry has the last say.