Fiat SpA's purchase of German peer Opel would be “an extraordinary opportunity” for the Italian carmaker, Fiat's chairman said in an interview published Sunday. A purchase of the troubled German unit of General Motors (GM.N) would be the “closing of the circle” following its partnership with Chrysler, Luca Cordero de Montezemolo told Corriere della Sera newspaper. Fiat Chief Executive Sergio Marchionne will meet German government officials in Berlin Monday to talk about an offer to buy Opel.