FIG. 5 illustrates an example node configuration for a network node configured to perform the above discussed operations. The network node 50 is configured for operation in a first network for designating one or more cells of a second network as neighbouring cells to the first network. The network node comprises radio circuitry 51 arranged for transmission and reception of radio signals; and processing circuitry 53 configured to cause the network node to perform the above disclosed operations. Thus, the processing circuitry is configured to cause the network node to select a set of carriers employed in the second network and to transmit, using the radio circuitry, information for the selected set of carriers to a wireless device served by a network node to receive, using the radio circuitry, measurement reports for respective carriers from the wireless device; and to determine neighbour cell relations between the first network and one or more cells of the second network based on the received measurement reports. According to an aspect of the disclosure, the processing circuitry comprises a processor S53a and a memory S53b storing the computer-executable instructions for execution in the processor S53a.