Method and apparatus for enhancing local id allocation for multiple end ues for ue-to-ue relay communication in a wireless communication system

A relay User Equipment (UE), comprising:

• a control circuit;
• a processor installed in the control circuit;
• and
• a memory installed in the control circuit and operatively coupled to the processor;
• wherein the processor is configured to execute a program code stored in the memory to:
• establish a first UE-to-UE (U2U) relay communication between a source end UE and a first target end UE and a second U2U relay communication between the source end UE and a second target end UE;
• and
• send a PC5 Radio Resource Control (RRC) message to the source end UE, wherein the PC5 RRC message includes a list information indicating at least one of a first mapping of a first local UE Identity (ID) and a first layer-2 ID for the first target end UE and a second mapping of a second local UE ID and a second layer-2 ID for the second target end UE.