A user terminal, UT, for a mobile satellite communications system, comprising: at least one processor; wherein, when initiating establishment of a radio connection, the processor is configured to control the UT to transmit a connection request message to a first satellite gateway, SGW, of the mobile satellite communications system, wherein the connection request message includes position information identifying a current location of the UT and a UT identifier, UTID; wherein the processor is further configured to process a connection setup message received by the UT in response to the connection request message, wherein the connection setup message includes a first tracking area identifier, TAID that identifies a one of a plurality of tracking areas that is associated with the current location of the UT; wherein the processor is further configured to, after processing the connection setup message, control the UT to transmit a connection complete message to the first SGW, together with an attach request message for a core network of the mobile satellite communications system, which includes the first TAID; wherein the processor is configured to control the UT to transmit a position verification message to the first SGW when the UT moves to a new location more than a predetermined threshold distance from its previously reported location, wherein the position verification message includes updated position information identifying a new location of the UT; wherein the processor is further configured to process a response message received by the UT in response to the position verification message, which includes either the first TAID when the new location of the UT is associated with the one tracking area or a second TAID that identifies another of the plurality of tracking areas that is associated with the new location of the UT; and wherein the processor is further configured to determine whether the response message includes the first TAID or the second TAID, and to control the UT to transmit a tracking area update message to the first SGW for the core network when it is determined that the response includes the second TAID, wherein the tracking area update message includes the second TAID. at least one processor; wherein, when initiating establishment of a radio connection, the processor is configured to control the UT to transmit a connection request message to a first satellite gateway, SGW, of the mobile satellite communications system, wherein the connection request message includes position information identifying a current location of the UT and a UT identifier, UTID; wherein the processor is further configured to process a connection setup message received by the UT in response to the connection request message, wherein the connection setup message includes a first tracking area identifier, TAID that identifies a one of a plurality of tracking areas that is associated with the current location of the UT; wherein the processor is further configured to, after processing the connection setup message, control the UT to transmit a connection complete message to the first SGW, together with an attach request message for a core network of the mobile satellite communications system, which includes the first TAID; wherein the processor is configured to control the UT to transmit a position verification message to the first SGW when the UT moves to a new location more than a predetermined threshold distance from its previously reported location, wherein the position verification message includes updated position information identifying a new location of the UT; wherein the processor is further configured to process a response message received by the UT in response to the position verification message, which includes either the first TAID when the new location of the UT is associated with the one tracking area or a second TAID that identifies another of the plurality of tracking areas that is associated with the new location of the UT; and wherein the processor is further configured to determine whether the response message includes the first TAID or the second TAID, and to control the UT to transmit a tracking area update message to the first SGW for the core network when it is determined that the response includes the second TAID, wherein the tracking area update message includes the second TAID.