A method of operating a terminal device in a wireless telecommunications system, the method comprising: determining first uplink control information should be transmitted using a first set of radio resources; determining the first uplink control information is associated with a first priority level; determining second uplink control information should be transmitted using a second set of radio resources; determining the second uplink control information is associated with a second priority level; determining if there is an overlap between the first and second sets of radio resources, and, in response to determining there is an overlap between the first and second sets of radio resources, multiplexing the first uplink control information and the second uplink control information by taking account of their respective priority levels; selecting a set of radio resources to use for transmitting the multiplexed first uplink control information and the second uplink control information; and transmitting the multiplexed first uplink control information and the second uplink control information using the selected set of radio resources; characterized in that wherein the selected set of radio resources to use for transmitting the multiplexed first uplink control information and the second uplink control information is a selected one of the first set of radio resources and the second set of radio resources; and wherein the selected one of the first set of radio resources and the second set of radio resources is the one which would result in the multiplexed first uplink control information and second uplink control information being transmitted with the lowest code rate. determining first uplink control information should be transmitted using a first set of radio resources; determining the first uplink control information is associated with a first priority level; determining second uplink control information should be transmitted using a second set of radio resources; determining the second uplink control information is associated with a second priority level; determining if there is an overlap between the first and second sets of radio resources, and, in response to determining there is an overlap between the first and second sets of radio resources, multiplexing the first uplink control information and the second uplink control information by taking account of their respective priority levels; selecting a set of radio resources to use for transmitting the multiplexed first uplink control information and the second uplink control information; and transmitting the multiplexed first uplink control information and the second uplink control information using the selected set of radio resources; characterized in that wherein the selected set of radio resources to use for transmitting the multiplexed first uplink control information and the second uplink control information is a selected one of the first set of radio resources and the second set of radio resources; and wherein the selected one of the first set of radio resources and the second set of radio resources is the one which would result in the multiplexed first uplink control information and second uplink control information being transmitted with the lowest code rate.