In 1927 and 1928, Voronca published two volumes of poetry in Paris, Colomba and Ulise ("Ulysses"). Colomba (entitled after his wife, Colomba Voronca) marked Voronca's new change in style, featuring joyous surrealist imagery. This imagistic style was adopted in the same time with Stephan Roll and the two influenced directly all the other poets in the unu group, even Geo Bogza initially. Ulise is considered by some critics (such as Ion Pop) his masterpiece (although G. Călinescu was confused by its eclectic style). Several of his works were illustrated with drawings by Constantin Brâncuşi, Marc Chagall, Robert Delaunay or Victor Brauner.
Eventually, Voronca was forced to resign from the group, as, on one hand, his 1931 book Incantații ("Incantations") was nomineed by the Society of Romanian Writers (considered "an elite of mercenaries" by Stephan Roll) and featured no longer poems written in free verse, while, on the other hand, Stephan Roll and Sașa Pană were increasingly involved in leftist politics (after the Aragon and Eluard incident that shook the French Surrealist group), condemning Voronca's lack of political involvement at the time.
He settled in France in 1933 and began writing and publishing in the French language. More than his Romanian poems, his poetry in French had a simple style (no longer heavily imagistic), now rooted in Walt Whitman and only slightly influenced by Surrealism. A French citizen in 1938, Voronca took part in the French Resistance. He visited Romania in January 1946, and was acclaimed for his writings and Anti-fascist activities. He never finished his Manuel du parfait bonheur ("Manual for Perfect Happiness"), committing suicide later in the same year. An edition of selected poems was published in France in 1956; it was followed ten years later by prints of never-published works. Sașa Pană oversaw a Romanian edition of many of Voronca's poems in 1972.