Reinforced optical fiber butt weld connection

A device for reinforcing the butt weld (5) of two optical fibres (1,2) in a telecommunications cable. The ends of the fibres are stripped. Said device comprises a metal capillary tube (6) which extends on either side of these ends along some length of the sheaths of the fibres. The capillary tube is made of a metal of high mechanical strength and surrounds the sheaths with little clearance. The remaining space (7,8) between the capillary tube and the stripped ends of the fibres and between the capillary tube and the sheaths of the fibres is filled with a slow-setting adhesive which is very fluid when in the liquid state and which sets in the absence of air.