Materazzi celebrated with his team-mates in the guise of Milan's patron and Italy's Prime Minister.
Italy's Minister of Defence, Ignazio La Russa, a renowned Inter fan, said: "Marco is a friend, but his actions were an enormous fall in style.
"I think that he didn't do it to give [a political] weight to his gesture. I have never seen anyone mock the President of a football team, not even Presidents as invasive as Berlusconi.
"And since Berlusconi is the Prime Minister, and Materazzi's gesture can be manipulated, I will call for Marco to apologise and make it understood that he didn't mean to offend the President."