A master node (MN) communicating with a UE using resource of a first band of unlicensed spectrum sends an addition request to a selected secondary node, to request resources for supporting the UE in a second band of unlicensed spectrum. The addition request includes minimum frequency separation information and optionally a baseline reference frequency. The minimum frequency separation information communicated in the addition request, indicates a minimum amount of frequency separation to be maintained between the communication resources in the first band of unlicensed spectrum used for communications with the UE and communication resource in the second band of unlicensed spectrum to be used for communications with the UE. The secondary node selects a channel within the second band of unlicensed spectrum to use for communications with the UE, which will satisfy the minimum frequency separation requirement communicated in the addition request and avoid IDC problems for the UE.