Techniques for controlling synchronous HARQ retransmissions are disclosed, in which non-adaptive retransmissions scheduled for a first transmission time interval are automatically deferred to a later transmission time interval in the event that a control message prohibiting the retransmission during the first transmission interval is received. In an exemplary method, a NACK message is received (320) in response to a previous data transmission corresponding to a stop-and-wait HARQ process, and a synchronous HARQ retransmission is scheduled (330) for a first transmission interval in response. A control message indicating that data for the stop-and-wait HARQ process may not be sent during the first transmission interval is received, and the synchronous HARQ retransmission is automatically deferred (350) to a second transmission interval, responsive to the control message. An explicit grant is not required to trigger the retransmission during the second transmission interval.