A group of Italian mayors has rebelled against Matteo Salvini, the country’s hardline interior minister, by refusing to implement stringent new laws on the treatment of asylum seekers.

The mayors of Palermo, Naples, Florence and Parma said that a controversial security law, passed by the populist coalition in November, violates the basic rights of migrants and refugees.

The law prevents migrants from seeking residency permits while they are waiting for their asylum applications to be considered, meaning that they cannot access services such as health care, housing and schools for their children.

The mayors are threatening to block the implementation of the law in their cities, in a major challenge to the populist coalition, which came to power in June.

The clash comes after Italy’s president, Sergio Mattarella, called for an end to the rancour prevalent in Italian politics and warned against the dangers of whipping up xenophobia, in a New Year’s Eve address that was watched on television by 10 million Italians.

Leoluca Orlando, the centre-Left mayor of Palermo, said the security decree was “inhumane”.