The disclosure relates to a method for providing, by a UE, feedback information of a retransmission protocol to a radio base station, the UE being configured with at least two cells. A least one cell bundling group is defined for the UE such that one of the at least one cell bundling group is associated with at least two out of the at least two cells. The UE communicates with the radio base station to receive downlink transmissions via at least one of the at least two cells. The UE operates a retransmission protocol with the radio base station to provide feedback information for the downlink communication. For each cell bundling group, the UE bundles feedback information generated in connection with those cells being associated with the respective cell bundling group so as to generate bundled feedback information per cell bundling group. The UE transmits the bundled feedback information of each cell bundling group to the radio base station.