The invention relates to an assembly for centring a first elongate tubular element and a second elongate tubular element, such as an underwater pile accommodated within a noise mitigation screen, at a common central longitudinal axis along which axis both the first and second element extend, and wherein the centre system is provided with first coupling element for fixedly coupling the centre system with one of the first and second tubular elements, and second coupling element for engaging the other tubular element for centring the other tubular element at the central axis.