"My presence in Liverpool was never planned," Salvini told reporters Thursday.
"What is going on there is not a gathering, but a dinner between League supporters in Liverpool - they are going to eat fish and chips," he said.
"It is the same kind of thing that our supporters did in Brazil, Switzerland, Belgium or Canada, and never before has a mayor intervened in a dinner among free citizens who are neither subversive or crazy. "
Salvini added that "Liverpool is a beautiful city" that he would like to visit one day, while inviting Rotheram to Milan "to eat osso buco or polenta".
"In this way, we will show him that Milan was not invaded by the fascists. I am sorry that someone passed judgment without knowing the facts. "
The Italian Senate on Wednesday officially authorized a criminal case against Salvini, who was kidnapped last year when, as interior minister, he prevented 131 migrants from disembarking from a coast guard vessel.
The Italian court of ministers in Catania, Sicily, decided in December that Salvini should be tried for allegedly depriving asylum seekers on the coast guard vessel Gregoretti of their freedom by refusing to allow them to leave.
"I did my homework," said Salvini on Thursday. "I think it's weird that they put me on trial. I'm not happy because I'm going to spend my days reading thousands of legal documents when I have a lot of things to do, like winning elections. "