A method including: establishing a first set of radio resources available for use by a terminal device for transmitting uplink data to a first network access node; establishing a shared set of radio resources available for use by the terminal device for transmitting uplink data to the first network access node and a second network access node; determining uplink data has become available for transmission; selecting radio resources to use for transmitting the uplink data from within the shared set of radio resources if it is determined the terminal device is in a boundary region between a first communication cell and a second communication cell; and selecting radio resources to use for transmitting the uplink data from within the first set of radio resources if it is determined the terminal device is within the first communication cell and not in the boundary region.