Translate the following English sentence to French:
"In spite of the efforts of the United Nations, in spite of MINURSO, in spite of the progress that has been made in compiling the electoral roll, the referendum keeps being postponed virtually sine die."
Malgré les efforts des Nations unies, malgré la Minurso, malgré les progrès réalisés dans l'élaboration du recensement, le référendum continue d'être reporté presque sine die.