The invention refers to providing a service controlled by a first server (1) of a first telecommunication network (1), the first server (1) performing the following steps: receiving a service request to provide a service with respect to a subscriber terminal –UE- (3), identifying that the service is to be supported by a second telecommunication network (2),and defining a plurality of consecutive actions, wherein the plurality of actions comprise a trigger to contact a second server (2) of the second telecommunications network (2) for providing a corresponding service support. The invention further refers to an application server (11, 21) and corresponding computer program.