The amount of interference to communications in Time Division Duplexing (TDD) mode between a TDD mobile and a TDD base station from a mobile operating in Frequency Division Duplexing (FDD) mode that is located near to the TDD base station can be reduced by passing information regarding the interfering FDD signal to the TDD base station, where it is processed and subtracted from the received TDD signal, which includes the interference, so as to obtain the pure TDD signal, as required. Either the FDD data (22), or an FDD signal (23) regenerated from the FDD data or simply the received FDD signal (21) can be passed (24) to the TDD base station. The TDD base station can regenerate an FDD signal, if required, which is then filtered (25) using TDD filters and normalized by correlating (26) and scaling (27) the filtered FDD signal to a received TDD signal. The normalized FDD signal is then subtracted (28) from the received TDD signal to reduce the interference.