A system and a method are disclosed for sidelink operations in unlicensed spectrum. In some embodiments, the method includes: receiving, by a first User Equipment (UE), a physical sidelink shared channel (PSSCH) transmission; refraining from sending an acknowledgment/negative acknowledgment (ACK/NACK) transmission, by the first UE, during a first Physical Sidelink Feedback Channel (PSFCH) occasion, wherein the refraining from sending occurs in response to an unsuccessful Listen Before Talk (LBT) attempt performed for the first PSFCH occasion; and sending an ACK/NACK transmission for the PSSCH transmission, during a second PSFCH occasion following the first PSFCH occasion.