A method (100) is disclosed, the method being performed in a network controller of a Mobile Transport Network. The Mobile Transport Network comprises communication links interconnecting network entities of a cellular Radio Access Network (RAN) and a core network. The method comprises receiving, from a network entity in the core network, an indication of traffic load within the RAN or between the RAN and the core network (102). Also disclosed is a method (200), performed in a network entity of a core network, the core network being connected to a cellular RAN by a Mobile Transport Network. The Mobile Transport Network comprises communication links interconnecting network entities of the core network and the RAN. The method (200) comprises sending to a network controller of the Mobile Transport Network an indication of traffic load within the RAN or between the RAN and the core network (202). Also disclosed are a network controller (300, 500), a core network entity (400, 600) and a computer program product configured to carry out methods in a network controller a core network entity.