how can i interrput the communication between coordinator and router?

I have a sensor network implemented with Arduino sending data to an Arduino coordinator through XBee S2. The coordinator is also connected via ethernet to a database, where i store the sampled values. The problem with it is that the ethernet-check routine takes up something like 60 s, resulting in a loss of packet as the RX buffer become full. Is there a way to tell the router to stop sending when the coordinator enter the connenction checking routine?