A steel cord, for use in the reinforcement of resilient articles such as rubber tyres, comprises a central bundle of wires surrounded by a circumferential layer of helicoidally twisted wires. In the central bundle, one can distinguish a core and a surrounding layer, the latter having the same twist pitch as the circumferential layer. In order to reduce wire migration, the wires of the central bundle show a limited number of relative position changes, between 2 and 300 per 30 cm cord length.