Apparatuses, methods, and systems are disclosed for V2X communication over multiple radio access types. One method includes supporting transmission of V2X messages over network connections for communication over multiple radio access types and network connections for direct V2X communication with other remote units over multiple radio access types. The method includes supporting V2X applications, wherein each V2X application uses the V2X messages transmitted via direct V2X communication over a radio access type and over a corresponding carrier frequency. The method includes supporting V2X applications, wherein each V2X application uses the V2X messages transmitted via the mobile communication network. The method includes receiving a request from a V2X application to transmit a message via the direct communication or via the mobile communication network. The method includes determining a transmission radio access type and a transmission carrier frequency for transmitting the message over direct communication.