A method of transmitting control information to a communication network, the method being implemented by a user equipment, UE, the method comprising: receiving, via radio resource control signaling, a configuration of at least two collections of uplink, UL, resources to be used for transmitting control information to the communication network; receiving an assignment of radio resources to be used for receiving a downlink, DL, transmission from a base station of the communication network; receiving an acknowledgement resource indication, ARI, indicating one of the configured collections of UL resources to be used for transmitting control information associated with the DL transmission; and transmitting the control information associated with the DL transmission to the base station on at least a subset of the indicated collection of UL resources, wherein the control information associated with the DL transmission comprises acknowledgement information associated with the DL transmission, wherein the indicated collection of UL resources comprises a plurality of selectable UL resource sets, the plurality of selectable UL resource sets including a first UL resource set for use in a first acknowledgement feedback mode of the communication network and a second UL resource set for use in a second acknowledgement feedback mode of the communication network, and wherein the control information associated with the DL transmission is transmitted on the one of the selectable UL resource sets which corresponds to the current acknowledgement feedback mode of the communication network, characterized in that, in the indicated collection of UL resources, the second UL resource set comprises the UL resources of the first UL resource set and UL resources in addition to those of the first UL resource set. receiving, via radio resource control signaling, a configuration of at least two collections of uplink, UL, resources to be used for transmitting control information to the communication network; receiving an assignment of radio resources to be used for receiving a downlink, DL, transmission from a base station of the communication network; receiving an acknowledgement resource indication, ARI, indicating one of the configured collections of UL resources to be used for transmitting control information associated with the DL transmission; and transmitting the control information associated with the DL transmission to the base station on at least a subset of the indicated collection of UL resources, wherein the control information associated with the DL transmission comprises acknowledgement information associated with the DL transmission, wherein the indicated collection of UL resources comprises a plurality of selectable UL resource sets, the plurality of selectable UL resource sets including a first UL resource set for use in a first acknowledgement feedback mode of the communication network and a second UL resource set for use in a second acknowledgement feedback mode of the communication network, and wherein the control information associated with the DL transmission is transmitted on the one of the selectable UL resource sets which corresponds to the current acknowledgement feedback mode of the communication network, characterized in that, in the indicated collection of UL resources, the second UL resource set comprises the UL resources of the first UL resource set and UL resources in addition to those of the first UL resource set.