 He was also an active participant in the further development of the European Union, taking an active part in the Single European Act Treaty negotiations in the mid-1980s, as well as the joint publication of the Genscher-Colombo plan with Italian Minister of Foreign Affairs Emilio Colombo which advocated further integration and deepening of relations in the European Union towards a more federal Europe.He later was among the politicians who pushed hard for monetary union alongside Edouard Balladur, France's finance minister, and Giuliano Amato, circulating a memorandum to that effect.Genscher retained his posts as foreign minister and vice chancellor through German reunification and until 1992 when he stepped down for health reasons.