The invention pertains to a process for manufacturing a (per)fluoropolymer, said process comprising polymerizing one or more fluorinated monomers in the presence of a multi-phase medium, said medium comprising: (A) a water phase [phase (W)]; (B) at least one fluorinated surfactant [surfactant (FS)] having formula (I) here below: Rf—(OCF2CF2)k-1—O—CF2—COOXa  (I) wherein Rf is a C1-C3 perfluoroalkyl group comprising, optionally, one or more ether oxygen atoms, k is 2 or 3 and Xa is a selected from a monovalent metal and an ammonium group of formula NRN4, wherein RN, equal or different at each occurrence, is a hydrogen atom or a C1-C3 alkyl group; (C) an oil phase [phase (O)] comprising: at least one non-functional (per)fluoropolyether (non-functional PFPE) comprising at least one (per)fluoropolyoxyalkylene chain [chain (RF)] and at least one functional (per)fluoropolyether (functional PFPE) comprising at least one (per)fluoropolyoxyalkylene chain [chain (R′F)] and having a number average molecular weight of at least 1000 and a solubility of less than 1% by weight in water at 25° C.