A method of a second User Equipment, in the following also referred to as UE, for transmitting a Sidelink Channel State Information, in the following also referred to as SL CSI,-report to a first UE, comprising: the second UE receives a second Sidelink Control Information in the following also referred to as SCI, from the first UE, wherein the second SCI schedules a second unicast sidelink transmission with Sidelink Channel State Information-Reference Signal(s), in the following also referred to as SL CSI-RS(s), to the second UE and the second SCI triggers the second UE to transmit the SL CSI-report to the first UE; the second UE performs measurement on the SL CSI-RS(s); the second UE derives the SL CSI-report based on the measurement; and the second UE generates a Medium Access Control Protocol Data Unit, in the following also referred to as MAC PDU, comprising a Medium Access Control Control Element, in the following also referred to as MAC CE, and sidelink data from one or more sidelink logical channels, wherein the sidelink data is available for transmitting to the first UE, characterized in that: the MAC CE comprises the SL CSI-report; and the method further comprises: the second UE sets a priority field in a first SCI to a fixed or pre-defined priority value of the MAC CE; and the second UE transmits the first SCI to the first UE, wherein the first SCI schedules a first unicast sidelink transmission for transmitting the MAC PDU. the second UE receives a second Sidelink Control Information in the following also referred to as SCI, from the first UE, wherein the second SCI schedules a second unicast sidelink transmission with Sidelink Channel State Information-Reference Signal(s), in the following also referred to as SL CSI-RS(s), to the second UE and the second SCI triggers the second UE to transmit the SL CSI-report to the first UE; the second UE performs measurement on the SL CSI-RS(s); the second UE derives the SL CSI-report based on the measurement; and the second UE generates a Medium Access Control Protocol Data Unit, in the following also referred to as MAC PDU, comprising a Medium Access Control Control Element, in the following also referred to as MAC CE, and sidelink data from one or more sidelink logical channels, wherein the sidelink data is available for transmitting to the first UE, characterized in that: the MAC CE comprises the SL CSI-report; and the method further comprises: the second UE sets a priority field in a first SCI to a fixed or pre-defined priority value of the MAC CE; and the second UE transmits the first SCI to the first UE, wherein the first SCI schedules a first unicast sidelink transmission for transmitting the MAC PDU. the MAC CE comprises the SL CSI-report; and the method further comprises: the second UE sets a priority field in a first SCI to a fixed or pre-defined priority value of the MAC CE; and the second UE transmits the first SCI to the first UE, wherein the first SCI schedules a first unicast sidelink transmission for transmitting the MAC PDU. the second UE sets a priority field in a first SCI to a fixed or pre-defined priority value of the MAC CE; and the second UE transmits the first SCI to the first UE, wherein the first SCI schedules a first unicast sidelink transmission for transmitting the MAC PDU.