A good way to achieve this is to have a Maven mirror server such as Sonatype Nexus. It is free and very easy to setup (Java web app). With Nexus one can have private (team, corporate etc) repository with a capability of deploying third party and internal apps into it, while also registering other Maven repositories as part of the same server. This way the local Maven settings would reference only the one private Nexus server and all the dependencies will be resolved using it.
