A mobile communication system comprises: a mobile platform (1) having a plurality of interfaces (2) to a respective plurality of mobile communication networks (6), and a router (5) for selectively connecting one or more communications devices (4) within the mobile platform (1) to one or more of the interfaces (2), for communication over the respective mobile communication networks (6); and a central core (10), common to each of the mobile communication networks (6), including a resource manager (11) arranged to allocate communication resources to the link interfaces (2); wherein the resource manager (11) is responsive to resource requests (S3) from the mobile platform (1) and to network conditions in the mobile communication networks (6).