The barbs between populist Italian politician Matteo Salvini and French President Emmanuel Macron were regular and personal. Last month, Italy's far-right interior minister and deputy prime minister said he hoped the French people could soon get rid of a "terrible president". Macron, on the other hand, has compared rising nationalism with leprosy, declaring that if populist nationalists consider him an enemy, they are "right".

The straw, which appeared to have broken the camel's back, came about in the form of a meeting between the other Italian MP, Luigi Di Maio, and the French populist, the Yellow West. The meeting, which took place on Tuesday just outside Paris, led Di Maio to explain that the wind of change had now crossed the Alps.

After France's decision to recall his ambassador, Di Maio tried to justify the meeting. "I wanted to meet with representatives of the Yellow West and the referendum referendum group because I do not believe that the future of European politics lies in the parties of the right or left wing," said Di Maio, chairman of the populist Five Star Movement , wrote in a letter published in Le Monde.

The diplomatic dispute now threatens to invade the world of art. Leonardo da Vinci's legacy – a long-standing cause of friction between Italy, where the Renaissance master spent most of his life, and France, where he sought refuge and died – is now being fought all the more violently.

The Louvre, where Da Vinci's most famous work, Mona Lisa, is admired daily by some 20,000 people, is planning an exhibition in October to commemorate the 500th anniversary of his death. Among other things, Rome was supposed to lend its name to the famous Vitruvian Man da Vinci, which is well-known to all, but is only seen by a few, since it is not normally exposed. Italian Culture Minister Lucia Borgonzoni threatened to terminate the loan, adding, "There are many things in the Louvre that should be returned to us, even beyond the old controversy surrounding the Mona Lisa."

Former Italian Prime Minister Enrico Letta, who has stopped practicing politics to teach him in Paris, says he has not been surprised after the last few years, but he warns that the consequences for both countries could be serious.

"France and Italy are the two superpowers of culture in Europe, we have to work together on big issues, the world has become much bigger than it was, today the world is huge, Italy and France, the European countries need to work together – that's why it is Fight really crazy, "said Letta to CNN.

It's no surprise that the source of the dispute was immigration. The first salvos were launched last summer at the height of the crisis with the lifeboat Aquarius. The ship used by SOS Méditerranée to pick up migrants from the Mediterranean has been prevented by the incoming populist Italian government from docking in the Sicilian ports that have been in use for years.

The water ship of the migrants shows a broken Europe

Italy had long argued that it was all about overcoming the crisis of European migrants. Complaints that fell on deaf ears. The populists decided to beat hard, which is why the French president accused them of acting "cynically and irresponsibly".

Likewise, Letta says, it's no wonder that the series is now just escalating. Just weeks before the European elections, Letta says, "you have to consider the choice of Macron, which was chosen as a shield against a major populist. [far-right politician Marine] Le Pen. The same divide that has been successful for him in France, believes that he can be successful in Europe. "

Regarding the populists in power in Rome, Letta says, "It's customary to build an enemy – without the enemy you can not be successful as a populist, so Macron is the perfect enemy for you – perfect target – you try this one To develop a narrative. "

All this means that reconciliation is unlikely, at least until the May elections. After that, much depends on the political landscape in Strasbourg and the relative weight of the populists and those who oppose them.

The dispute could now jeopardize the future of Europe itself.