Two-component fibres, having a surface area of at least 1 m 2 /g, suited for replacing cellulose fibres in the manufacture of paper and paper-like products, comprise a core of olefinic polymer and from 2 to 50% by weight of a sheath of a hydrophilic polymer, and exhibit values of tenacity higher than 3,000 meters and cohesion higher than 300 meters. They are prepared by extruding a stable emulsion formed by a mixture of a solution of the olefinic polymer with a solution of hydrophilic polymer in reciprocally immiscible solvents, at a temperature exceeding the boiling temperature of the solvent of the olefinic polymer and at least equal to the dissolution temperature of such polymer in such solvent, in a medium at a lower pressure.