He returned in the government in 1966 as Economy and Finance Minister. After the May 1968 crisis, he became Foreign Minister, then, one year later, he served as Defence Minister of President Georges Pompidou. In that role, he became a hated figure of the left, because of his determination to expropriate the land of 107 peasant farmers and Shepherds on the Larzac plateau, to extend an existing military base. The resulting civil disobedience campaign was ultimately victorious. Considered as a guardian of the Gaullist orthodoxy, he was marginalized after the election of Valéry Giscard d'Estaing as President of France in 1974. He criticized with virulence his foreign policy. In 1979 he took a major part in the Rally for the Republic (RPR) campaign against the European federalism and was elected member of the European Parliament in order to defend the principle of Europe of nations. But later, he accused Jacques Chirac and the RPR lead to moderate their speech, and so, he was a dissident candidate in the 1981 presidential election. He obtained only 1.6% of votes.