Treaty negotiations are underway, and both parties have agreed to accept whatever boundaries are demarcated [dɪˈmɑrˌkeɪt] in that document.

demarcate
verb [dɪˈmɑrˌkeɪt]

To demarcate something is
1) to fix
2) define its limits or edges.

thank Spanish for both: the Spanish noun demarcación (from demarcar, "to delimit") was used in 1493 to name a meridian dividing New World territory between Spain and Portugal.

English