A method used in a User Equipment, UE, for reporting Hybrid Automatic Repeat Request acknowledgement/non-acknowledgement, HARQ ACK/NACK, for Physical Downlink Shared Channels, PDSCHs, in dynamic time division duplex, TDD, configurations, the method comprising: receiving a plurality of PDSCHs in DownLink, DL, subframes associated with an UpLink, UL, subframe and indicated by a DL reference TDD configuration; dividing the DL subframes into a first subset of DL subframes and a second subset of DL subframes, wherein the first subset of DL subframes is also indicated by an UL reference TDD configuration; assigning a first set of Physical Uplink Control Channel, PUCCH, resource indices based on resources used in transmission of Physical Downlink Control Channels, PDCCHs, corresponding to the PDSCHs received in the DL subframes of the first subset of DL subframes; assigning a second set of PUCCH resource indices based on resources used in transmission of PDCCHs corresponding to the PDSCHs received in the DL subframes of the second subset of DL subframes; and for each of the received PDSCHs, reporting HARQ ACK/NACK using PUCCH resources in an order of the assigned first set of PUCCH resource indices for PDSCHs received in the DL subframes of the first subset of DL subframes and in an order of the assigned second set of PUCCH resource indices for PDSCHs received in the DL subframes of the second subset of DL subframes, characterized in that assigning the first set of PUCCH resource indices and the second set of PUCCH resource indices are based on the following formula: n PUCCH, i 1 = M q − i − 1 ⋅ N c + i ⋅ N c + 1 + n CCE, i + N PUCCH q, wherein n PUCCH, i 1 is a PUCCH resource index determined based on resources used in transmission of PDCCHs corresponding to the PDSCHs received in the DL subframe that is the i th element of the q th subset, M q is the total number of DL subframes in the q th subset, 0≤ i < M q, c is selected from {0,1,2,3} such that N c ≤ n CCE,i < N c +1, N c = max 0 ⌊ N RB DL ⋅ N sc RB ⋅ c − 4 / 36 ⌋ where N RB DL is the number of physical resource blocks, PRBs, in each downlink subframe and where N sc RB is the number of subcarriers in each physical resource block, n CCE,i is the sequence number of the first Control Channel Element, CCE, used for transmission of the corresponding PDCCH in subframe n − k i q, k i q q = 0, 1 is the i th element of the q th subset, n indicates the UL subframe associated with the DL subframes where the plurality of PDSCHs are received, N PUCCH q q = 0, 1 is an offset for q th subset, wherein q=0 corresponds to one of the first and second subsets of DL subframes and q=1 corresponds to the other one of the first and second subsets of DL subframes. receiving a plurality of PDSCHs in DownLink, DL, subframes associated with an UpLink, UL, subframe and indicated by a DL reference TDD configuration; dividing the DL subframes into a first subset of DL subframes and a second subset of DL subframes, wherein the first subset of DL subframes is also indicated by an UL reference TDD configuration; assigning a first set of Physical Uplink Control Channel, PUCCH, resource indices based on resources used in transmission of Physical Downlink Control Channels, PDCCHs, corresponding to the PDSCHs received in the DL subframes of the first subset of DL subframes; assigning a second set of PUCCH resource indices based on resources used in transmission of PDCCHs corresponding to the PDSCHs received in the DL subframes of the second subset of DL subframes; and for each of the received PDSCHs, reporting HARQ ACK/NACK using PUCCH resources in an order of the assigned first set of PUCCH resource indices for PDSCHs received in the DL subframes of the first subset of DL subframes and in an order of the assigned second set of PUCCH resource indices for PDSCHs received in the DL subframes of the second subset of DL subframes, characterized in that assigning the first set of PUCCH resource indices and the second set of PUCCH resource indices are based on the following formula: