Translate the following English sentence to French:
"The Tampere conclusions noted that the Union needed a comprehensive approach to the phenomenon of immigration, which is clearly linked to a whole series of political questions which have remained unanswered."
Les conclusions de Tampere ont démontré la nécessité d' une approche globale du phénomène de l' immigration qui, bien entendu, est lié à une longue série de questions politiques restées sans réponse.