The invention provides a method for assisting handover of a user terminal's, UT's, communication session in an integrated multi RAT network, said method to be carried out by an RNCI being installed in said network, said method comprising the following steps:— receiving a “Handover Candidate” message comprising a message type identifier information element identifying said message as being a “Handover Candidate” message and which message identifies said session and which message further identifies a candidate RNC of said network, wherein said candidate RNC constitutes an RNC handover candidate for said session,— establishing the identity of said RNC by investigating said message,— associating said communication session with said candidate RNC identified in the previous step. The invention provides an RNC1, RNC2, and software, realising the method according to the invention.