The present document specifies the Inter-Chip USB interface between the USB UICC and the USB UICC-enabled terminal@ subsequently referred to as the IC USB interface. It describes: ? the characteristics of the Inter-Chip USB electrical interface between the USB UICC and the USB UICC-enabled terminal; ? the initial communication establishment and the transport protocols; ? the communication layers between the USB UICC and the USB UICC-enabled terminal. The physical characteristics (including mechanical aspects) defined in TS 102 221 [1] apply to USB UICCs. The present document comes as an extension of TS 102 221 [1] complementing the electrical characteristics of contacts C1 and C5 and describing the behaviour of contacts C4 and C8 when the USB interface is supported. The Inter-Chip USB interface provides access to the existing UICC resources such as the file system and security features specified in TS 102 221 [1] and to other resources and functionalities specified in the present document.