In this paper, a two-user interference channel with multiple relays (IFC-MR) is studied. The two sources transmit signals to their respective receivers simultaneously with the cooperation of multiple full-duplex relays. Each terminal is equipped with a single antenna. The diversity-multiplexing tradeoff (DMT) upper bound of the channel is first determined by using the capacity cut-set upper bound, and a transmission scheme is then suggested to achieve this DMT upper bound. To be specific, a decoding set is formed by all the relays that can jointly decode signals from both sources. Out of this decoding set, each destination chooses a relay with the best relay-destination channel condition to forward signals. In case both destinations identify the same relay for forwarding, it transmits the superposition of the two decoded signals. Eventually, the optimal DMT of the two-user IFC-MR is realized.