A method performed by medium access control, MAC, layer of a communication device for providing data to be transmitted to another communication device within a radio communications network, wherein the MAC layer receives first and second data from a higher layer with respect to the MAC layer, comprising: - assigning the first data to a first transport block; - assigning the second data to a second transport block; and - transmitting the first transport block and the second transport block to a lower layer with respect to the MAC layer, wherein the assigning of the second data to the second transport block is performed before the assigning for the first transport block has been completed or while the first transport block has remaining capacity for data, wherein the first data and the second data are received from a first logical channel having a first priority, and wherein further data is received from a second logical channel having a second priority, wherein the first priority is higher than the second priority, wherein the first data and the second data are assigned first to the first and the second transport block, and wherein subsequently the further data is assigned to the second transport block if there are still available transport blocks or parts of transport blocks that have not been used for the assigning of the data of the first logical channel. - assigning the first data to a first transport block; - assigning the second data to a second transport block; and - transmitting the first transport block and the second transport block to a lower layer with respect to the MAC layer, wherein the assigning of the second data to the second transport block is performed before the assigning for the first transport block has been completed or while the first transport block has remaining capacity for data, wherein the first data and the second data are received from a first logical channel having a first priority, and wherein further data is received from a second logical channel having a second priority, wherein the first priority is higher than the second priority, wherein the first data and the second data are assigned first to the first and the second transport block, and wherein subsequently the further data is assigned to the second transport block if there are still available transport blocks or parts of transport blocks that have not been used for the assigning of the data of the first logical channel. wherein the assigning of the second data to the second transport block is performed before the assigning for the first transport block has been completed or while the first transport block has remaining capacity for data, wherein the first data and the second data are received from a first logical channel having a first priority, and wherein further data is received from a second logical channel having a second priority, wherein the first priority is higher than the second priority, wherein the first data and the second data are assigned first to the first and the second transport block, and wherein subsequently the further data is assigned to the second transport block if there are still available transport blocks or parts of transport blocks that have not been used for the assigning of the data of the first logical channel.