A method for allocating space for a plurality of control sets for Hybrid Automatic Repeat Request (HARQ), wherein each control set comprising elements for carrying HARQ indicators. The method is performed in a network node and comprises determining a largest set size, in number of resources, of any one of the plurality of control sets; determining a target size, in number of resources, to be allocated for HARQ; allocating a HARQ space, wherein the HARQ space having a size, in number of resources, being a maximum of the largest set size and the target size; and spreading the plurality of control sets within the HARQ space. The HARQ space can be used in the uplink, for providing HARQ feedback on downlink information.