A radio communication system for handover during Dual Connectivity, the radio communication system comprising: a radio network including a first radio station configured to serve a first cell, a second radio station configured to serve a second cell, and a third radio station configured to serve a third cell; and a radio terminal having a capability of Dual Connectivity using either the first cell or the third cell as a primary cell (S1701, S1713) with the second cell as a secondary cell (S1702, S1715), wherein the first radio station is configured to determine a handover to the third cell, to send a handover request message to the third radio station and to receive a handover request acknowledgement from the third radio station, the first radio station is configured to send, to the second radio station, a request to suspend communicating with the radio terminal, the second radio station is configured to suspend communicating with the radio terminal, and to transmit, to the first base station, an acknowledgement of the request, the first radio station is configured to transmit, to the radio terminal, a Radio Resource Control, RRC, Connection Reconfiguration message to instruct handover from the first cell to the third cell while communication status information of the secondary cell is kept, the radio terminal is configured to change the primary cell from the first cell to the third cell while the communication status information of the secondary cell is kept, to synchronize to the third radio station and to transmit an RRC Connection Reconfiguration complete message to the third radio station, the first radio station is configured to send, to the third radio station, a Transfer message and receive a User Equipment, UE, context release message from the third radio station, and the second radio station is configured to receive, from the third radio station, an instruction to resume communication with the radio terminal, after the radio terminal synchronizes to the third radio station and the third radio station receives the RRC Connection Reconfiguration Complete message from the radio terminal, characterised in that the Transfer message is a Sequence Number, SN, Status Transfer message. a radio network including a first radio station configured to serve a first cell, a second radio station configured to serve a second cell, and a third radio station configured to serve a third cell; and a radio terminal having a capability of Dual Connectivity using either the first cell or the third cell as a primary cell (S1701, S1713) with the second cell as a secondary cell (S1702, S1715), wherein the first radio station is configured to determine a handover to the third cell, to send a handover request message to the third radio station and to receive a handover request acknowledgement from the third radio station, the first radio station is configured to send, to the second radio station, a request to suspend communicating with the radio terminal, the second radio station is configured to suspend communicating with the radio terminal, and to transmit, to the first base station, an acknowledgement of the request, the first radio station is configured to transmit, to the radio terminal, a Radio Resource Control, RRC, Connection Reconfiguration message to instruct handover from the first cell to the third cell while communication status information of the secondary cell is kept, the radio terminal is configured to change the primary cell from the first cell to the third cell while the communication status information of the secondary cell is kept, to synchronize to the third radio station and to transmit an RRC Connection Reconfiguration complete message to the third radio station, the first radio station is configured to send, to the third radio station, a Transfer message and receive a User Equipment, UE, context release message from the third radio station, and the second radio station is configured to receive, from the third radio station, an instruction to resume communication with the radio terminal, after the radio terminal synchronizes to the third radio station and the third radio station receives the RRC Connection Reconfiguration Complete message from the radio terminal, characterised in that the Transfer message is a Sequence Number, SN, Status Transfer message.