A method for a User Equipment, UE, transmitting uplink control information in a wireless communication system supporting carrier aggregation and operating in Time Division Duplex, TDD, comprising: receiving at least one of one or more Physical Downlink Control Channels, PDCCHs, and one or more Physical Downlink Shared Channels, PDSCHs, in a plurality of downlink subframes according to a UL-DL configuration: determining the number of bits of acknowledgement/negative acknowledgement, ACK/NACK, information required as the ACK/NACK information for the at least one of the one or more PDCCHs and the one or more PDSCHs by using a value indicated by a predetermined 2-bit field in a Downlink Control Information, DCI, format for UL scheduling; and transmitting the ACK/NACK information through a Physical Uplink Shared Channel, PUSCH, corresponding to the DCI format, said method characterised in that the number of bits of the ACK/NACK information is derived from Nmax, CC, which is a maximum number from among the numbers of PDSCHs and PDCCHs transmitted in the plurality of downlink subframes for respective component carriers and is equal to V DAI UL + 4 ⌈ U max − V DAI UL / 4 ⌉ wherein V DAI UL denotes the value indicated by the predetermined 2-bit field and is an integer in the range of 1 to 4, U max denotes a maximum value from among the numbers of PDSCHs and PDCCHs received in the plurality of downlink subframes for respective component carriers and ┌ ┐ represents a ceiling function. receiving at least one of one or more Physical Downlink Control Channels, PDCCHs, and one or more Physical Downlink Shared Channels, PDSCHs, in a plurality of downlink subframes according to a UL-DL configuration: determining the number of bits of acknowledgement/negative acknowledgement, ACK/NACK, information required as the ACK/NACK information for the at least one of the one or more PDCCHs and the one or more PDSCHs by using a value indicated by a predetermined 2-bit field in a Downlink Control Information, DCI, format for UL scheduling; and transmitting the ACK/NACK information through a Physical Uplink Shared Channel, PUSCH, corresponding to the DCI format, said method characterised in that the number of bits of the ACK/NACK information is derived from Nmax, CC, which is a maximum number from among the numbers of PDSCHs and PDCCHs transmitted in the plurality of downlink subframes for respective component carriers and is equal to V DAI UL + 4 ⌈ U max − V DAI UL / 4 ⌉ wherein V DAI UL denotes the value indicated by the predetermined 2-bit field and is an integer in the range of 1 to 4, U max denotes a maximum value from among the numbers of PDSCHs and PDCCHs received in the plurality of downlink subframes for respective component carriers and ┌ ┐ represents a ceiling function. determining the number of bits of acknowledgement/negative acknowledgement, ACK/NACK, information required as the ACK/NACK information for the at least one of the one or more PDCCHs and the one or more PDSCHs by using a value indicated by a predetermined 2-bit field in a Downlink Control Information, DCI, format for UL scheduling; and transmitting the ACK/NACK information through a Physical Uplink Shared Channel, PUSCH, corresponding to the DCI format, said method characterised in that the number of bits of the ACK/NACK information is derived from Nmax, CC, which is a maximum number from among the numbers of PDSCHs and PDCCHs transmitted in the plurality of downlink subframes for respective component carriers and is equal to V DAI UL + 4 ⌈ U max − V DAI UL / 4 ⌉ wherein V DAI UL denotes the value indicated by the predetermined 2-bit field and is an integer in the range of 1 to 4, U max denotes a maximum value from among the numbers of PDSCHs and PDCCHs received in the plurality of downlink subframes for respective component carriers and ┌ ┐ represents a ceiling function.