(ANSA) - Milan, December 16 - Interior Minister Angelino Alfano on Monday said Milan Expo 2015 will be ''mafia free'' during a meeting in the Milan prefecture with the Italian parliament's anti-mafia commission. ''We will demonstrate that we will succeed in organising a great event without the participation of the mafia groups and without mafia profits,'' Alfano declared. Alfano thanked Milan Mayor Giuliano Pisapia and Lombardy Governor Roberto Maroni for monitoring preparations to prevent mafia infiltration, and recalled how a number of companies were excluded from bidding as contractors for Expo 2015. Maroni was not invited to the meeting - an omission that prompted the delegation from Maroni's Northern League party to boycott it. ''It is truly absurd that various representatives of local institutions were invited, but not Governor Maroni,'' said Northern League Senator Raffaele Volpi. ''The failure of to involve the governor of Lombardy represents not only an institutional snub, but a serious, reprehensible, incomprehensible failing,'' Volpi added. Maroni will be heard by the parliament antimafia commission in Rome in January, the office of commission president, Rosy Bindi, said in a statement. Bindi, who is also whip for the centre-left Democratic Party (PD), made the arrangement with Maroni on Monday, the statement added.