Lollobrigida under fire for stopping Frecciarossa train.

Italy's minister for agriculture on Tuesday reportedly ordered a high-speed train to make an unscheduled stop near Rome, so that he could get off, after the Naples-bound train got delayed.

Francesco Lollobrigida, who is the brother-in-law of Italian premier Giorgia Meloni, forced the train to make an impromptu stop at Ciampino, reports Il Fatto Quotidiano newspaper.

The southbound Frecciarossa 9519 train from Turin was already running late time when it arrived in Rome's Termini station, where Lollobrigida and his staff got on at around midday.

The minister was headed to the Napoli Afragola station from where he was set to travel to Caivano, a town near Naples, for the inauguration of a new park.

However the train encountered further delays after leaving Termini, due to a fault on the high-speed line just south of Rome.

This led Trenitalia to divert all Frecce and Intercity trains to the old Rome-Naples line, with a passenger on board telling Il Fatto Quotidiano that it took "more than an hour" to make the roughly 15-km journey to Ciampino.

The "extraordinary stop" for Lollobrigida was allegedly authorised by the Italian railway infrastructure management company Rete Ferroviaria Italiana, Il Fatto Quotidiano reports.

The minister and his entourage were reportedly met at Ciampino by a government car and driven to Caivano to make the appointment on time.

The incident sparked fierce criticism on Wednesday from the opposition.

"If Minister Lollobrigida really stopped a high-speed train in a station on the Rome-Naples route and got off and then continued by car, we are in the presence of an unprecedented abuse of power" - said former Italian premier and Italia Viva leader Matteo Renzi - "Ministers can use state vehicles but cannot stop the trains of all citizens. If the news is confirmed we will seek Lollobrigida's resignation."

Andrea Casu of the centre-left Partito Democratico (PD) slammed the reported incident as "an act of unjustifiable arrogance, a slap in the face of all the citizens who were on the same train as him, already late, and to all the people who face every day the inefficiencies caused by the lack of transport funding from the Meloni government of which he is a part."