Urso also dismissed assertions that the decree was illegal, saying what was illegal was the conduct of an airline that “has been punished 11 times by the competition and market authority for having breached the market rules and the rights of consumers of this country”.

The decree, passed last month, effectively caps fares to Sicily and Sardinia.

It clamps down on the use of algorithms to set flight prices amid claims that they were responsible for soaring fares in the summer.

“The price decree is based on rubbish data,” O’ Leary said as he presented the company’s winter services, arguing civil-aviation authority ENAC had given the government “false, inaccurate advice”.

“It is a stupid, idiotic decree, which will reduce flights by increasing fares.

“We have already reduced flights by 10 per cent to Sardinia and we will do this same for Sicily this winter.”

He added that the only new routes Ryanair would operate from Italy this winter would be international services, not domestic ones.

ENAC President Pierluigi Di Palma said O’Leary’s comments were “surreal”.

He said an “oligopoly” had formed in the Italian domestic air-transport market, “particularly in the case of Ryanair, which has bought other companies like Air Malta”.

“It’s clear there is a no longer a free market, but the imposition of the price and little consumer protection.”

Antitrust Authority President Roberto Rustichelli, meanwhile, told a Senate hearing that the decree did not hinder airlines’ ability to “independently set their price policies” adding that it appeared to try to impede “illegal exploitation of market power to the damage of particularly vulnerable consumers”.

ANSA