A method in a network node for supporting a predetermined set of aggregation levels for configuration of a downlink control channel for one of a slot Transmission Time Interval (TTI) and a subslot TTI. The method includes determining an aggregation level to be monitored by a wireless device (WD) in a communication network; and determining a number of downlink control channel candidates for the WD to monitor within each of the one of the slot TTI and the subslot TTI, the number of downlink control channel candidates based upon the aggregation level. A wireless device and corresponding method for supporting a predetermined set of aggregation levels and for implementing at least one aggregation level and at least one downlink control channel candidate for configuration of a downlink control channel for one of a slot TTI and a subslot TTI are also provided.