Migration, which brought the Italian populists to power, is at the heart of the dispute.

On Thursday, Mr. Salvini responded to the French ambassador’s recall with a series of complaints, including France’s closing of its border to stop illegal migrants passing through Italy.

‘‘Stop with pushbacks at the borders,’’ said Mr. Salvini, who leads the anti-immigrant League party, the Italian government’s coalition partner. ‘‘There have been about 60,000 since 2017, and those include children and women abandoned in the forest.’’

French officials say the number is closer to 50,000. They noted that the border patrols were put in place in November 2015, after the terrorist attacks in Paris, and that under European Union agreements illegal migrants should be brought back to the country where they were first registered.

“The policy disagreements between Italy and France were present even during the previous government, especially on immigration, but it never reached this level,” said Nathalie Tocci, director of the Rome-based think-tank Institute of International Affairs, said in a phone interview. “It greatly exacerbated in the last three months.”

“This is also cast against the broader E.U. story, of the big dividing line between national sovereigntists and European sovereigntists,” she said.

The dispute came to a boil last summer over the migrant issue. The Italians, having borne the brunt of the migrant wave since 2015, were outraged last year when Mr. Macron denounced the new Italian government for failing to take in hundreds of migrants aboard the Aquarius humanitarian rescue boat.

The Italian prime minister’s office reacted with fury, saying it could not “accept hypocritical lessons from a country that, on migration, has always preferred to turn its back on its partners.” And it was true that France has made a regular practice of blocking migrants crossing the Italian border.