A method performed by a user equipment, UE, the method comprising: the UE transmitting a first access network, AN, message comprising a first registration request comprising registration type information indicating that the UE wants to perform an initial registration or a registration update; the UE receiving a registration accept that is responsive to the registration request, wherein the registration accept was transmitted by a serving access and mobility management function, AMF, and comprises first information indicating that a Mobile Initiated Connection Only, MICO, mode of operation is allowed and second information indicating that the UE's registration area encompasses an entire PLMN; the UE deciding to initiate a connection or perform a periodic registration update; and the UE determining whether the UE is located within an area served by the serving AMF, wherein the UE is configured such that: i) as a result of the UE deciding to initiate the connection and determining that the UE is not located within an area served by the serving AMF, the UE transmits a second registration request comprising registration type information indicating that the UE wants to perform a mobility registration update, and ii) as a result of the UE deciding to initiate the connection and determining that the UE is located within an area served by the serving AMF, the UE transmits towards the serving AMF a service request message. the UE transmitting a first access network, AN, message comprising a first registration request comprising registration type information indicating that the UE wants to perform an initial registration or a registration update; the UE receiving a registration accept that is responsive to the registration request, wherein the registration accept was transmitted by a serving access and mobility management function, AMF, and comprises first information indicating that a Mobile Initiated Connection Only, MICO, mode of operation is allowed and second information indicating that the UE's registration area encompasses an entire PLMN; the UE deciding to initiate a connection or perform a periodic registration update; and the UE determining whether the UE is located within an area served by the serving AMF, wherein the UE is configured such that: i) as a result of the UE deciding to initiate the connection and determining that the UE is not located within an area served by the serving AMF, the UE transmits a second registration request comprising registration type information indicating that the UE wants to perform a mobility registration update, and ii) as a result of the UE deciding to initiate the connection and determining that the UE is located within an area served by the serving AMF, the UE transmits towards the serving AMF a service request message. i) as a result of the UE deciding to initiate the connection and determining that the UE is not located within an area served by the serving AMF, the UE transmits a second registration request comprising registration type information indicating that the UE wants to perform a mobility registration update, and ii) as a result of the UE deciding to initiate the connection and determining that the UE is located within an area served by the serving AMF, the UE transmits towards the serving AMF a service request message.