For a push-to-talk function in a mobile communication system (30), an indication is received (35) by a user (50) that the talking floor is available. Next, an uplink temporary block flow is established (36). Prior to release of the uplink temporary block flow by the mobile communication system, a refresh message is sent (39) to hold the uplink temporary block flow. Downlink temporary block flows may also be refreshed by this method, or by the mobile communication system. Then the requesting user may enable the push-to-talk function. These techniques can improve talker arbitration and call setup delays for push-to-talk.