A function \(Q\) is in the generalised Nevanlinna class \(N(k)\) if it is meromorphic in \(\mathbb{C}^+ \cup\mathbb{C}^-\), symmetric with respect to the real axis and if the kernel \((Q(z)-\overline {Q(t)})/(z- \overline t),z,t\) in the intersection of the domain of holomorphy of \(Q\) with \(\mathbb{C}^+\), has \(k\) negative squares. Using an integral representation of \(Q\) proved by [\textit{K. Daho} and \textit{H. Langer}, Math. Nachr. 120, 275-294 (1985; Zbl 0567.47030)], the authors prove a relation of the type \(Q_1(z)={(z-\alpha) (z-\overline \alpha) \over(z-\beta) (z-\beta)}Q(z)\), where \(Q_1\) is in \(N(k-1)\), provided \(Q\) has (generalised) zero \(\beta\) and pole \(\alpha\) satisfying certain conditions.