In later years, he was an opponent of the proletariat's dictatorship and an oppositionist. Because of his participation in 1956 uprising he was sentenced to eight years in prison, of which he served three and a half (until the 1960 amnesty). After his release he was banned from publication, because of which he concentrated on translating works of Goethe, Heine, Brecht, Shakespeare, Ginsberg, Shelley, Keats, Pushkin, Jandl and Lorca.