A first base station, comprising: a transceiver configured to transmit and receive a signal; and a controller configured to: transmit, via the transceiver to a second base station, a message requesting an inter-radio access technology, RAT, handover of a user equipment, UE, from an evolved-universal mobile telecommunication system terrestrial radio access network, E-UTRAN, cell of the first base station to a Global System for Mobile Communications, GSM, Enhanced Data rates for GSM Evolution, EDGE, radio access network, GERAN, cell of the second base station, the message including inter-RAT measurement configuration information and at least one of a source base station subsystem, BSS, to target BSS transparent container or an old BSS to new BSS information element, the at least one of the source BSS to target BSS transparent container or the old BSS to new BSs information element including a tracking area identity, TAI, of the E-UTRAN cell the first base station, an identifier of the first base station, and an identifier of the E-UTRAN cell of the first base station, receive (345, 347, 349), via the transceiver from the second base station, a handover report indicating that the inter-RAT handover is unnecessary, the handover report including the identifier of the E-UTRAN cell of the first base station, and determine whether the handover report is valid and, if it is valid, process the handover report and, if it is not valid, ignore the handover report, wherein the inter-RAT measurement configuration information includes information on a duration in which the second base station is to collect measurement results after a successful inter-RAT handover and information on a frequency for which the second base station collects the measurement results received from the UE by instructing the UE to measure the frequency, and wherein an operation mode of the second base station is a GERAN A/Gb mode. a transceiver configured to transmit and receive a signal; and a controller configured to: transmit, via the transceiver to a second base station, a message requesting an inter-radio access technology, RAT, handover of a user equipment, UE, from an evolved-universal mobile telecommunication system terrestrial radio access network, E-UTRAN, cell of the first base station to a Global System for Mobile Communications, GSM, Enhanced Data rates for GSM Evolution, EDGE, radio access network, GERAN, cell of the second base station, the message including inter-RAT measurement configuration information and at least one of a source base station subsystem, BSS, to target BSS transparent container or an old BSS to new BSS information element, the at least one of the source BSS to target BSS transparent container or the old BSS to new BSs information element including a tracking area identity, TAI, of the E-UTRAN cell the first base station, an identifier of the first base station, and an identifier of the E-UTRAN cell of the first base station, receive (345, 347, 349), via the transceiver from the second base station, a handover report indicating that the inter-RAT handover is unnecessary, the handover report including the identifier of the E-UTRAN cell of the first base station, and determine whether the handover report is valid and, if it is valid, process the handover report and, if it is not valid, ignore the handover report, wherein the inter-RAT measurement configuration information includes information on a duration in which the second base station is to collect measurement results after a successful inter-RAT handover and information on a frequency for which the second base station collects the measurement results received from the UE by instructing the UE to measure the frequency, and wherein an operation mode of the second base station is a GERAN A/Gb mode. transmit, via the transceiver to a second base station, a message requesting an inter-radio access technology, RAT, handover of a user equipment, UE, from an evolved-universal mobile telecommunication system terrestrial radio access network, E-UTRAN, cell of the first base station to a Global System for Mobile Communications, GSM, Enhanced Data rates for GSM Evolution, EDGE, radio access network, GERAN, cell of the second base station, the message including inter-RAT measurement configuration information and at least one of a source base station subsystem, BSS, to target BSS transparent container or an old BSS to new BSS information element, the at least one of the source BSS to target BSS transparent container or the old BSS to new BSs information element including a tracking area identity, TAI, of the E-UTRAN cell the first base station, an identifier of the first base station, and an identifier of the E-UTRAN cell of the first base station, receive (345, 347, 349), via the transceiver from the second base station, a handover report indicating that the inter-RAT handover is unnecessary, the handover report including the identifier of the E-UTRAN cell of the first base station, and determine whether the handover report is valid and, if it is valid, process the handover report and, if it is not valid, ignore the handover report, wherein the inter-RAT measurement configuration information includes information on a duration in which the second base station is to collect measurement results after a successful inter-RAT handover and information on a frequency for which the second base station collects the measurement results received from the UE by instructing the UE to measure the frequency, and wherein an operation mode of the second base station is a GERAN A/Gb mode.