An apparatus of a Next Generation Node-B (gNB) with a CP-UP separation includes processing circuitry configured to decode a radio resource control (RRC) request message from the UE for establishing a connection between the UE and a UPF of a 5G NR architecture in a network slice. In response to a confirmation message that the UE is authorized to communicate via the network slice, encode a Central Unit User plane (CU-UP) resource status request message for transmission by a Central Unit Control Plane (CU-CP) entity of the gNB to a plurality of CU-UP entities. A CU-UP resource status response message from each of the plurality of CU-UP entities is decoded at the CU-CP entity. The resource status response message including resource availability information for the CU-UP entities. A CU-UP entity is selected by the CU-CP entity from the plurality of CU-UP entities based on the resource availability information.