Shipment Transit times - LOV for Country for origin type 'Region'

Hello All

Need help to understand from where the values in the LOV for "Country" gets populated in shipment transit times form when the Origin type is "Region"

Below is the Navigation

OM Responsibility -> Setups -> Shipping ->Freight Carriers, Cost Types --> Shipment Transit time    under this when you try to add a new value select "Origin Type" as "Region" , in 'Origin' there is a LOV for 'Country' . I want to add a new country to the list. Could anyone help me know from where do we input a new value in this LOV.

Thanks

AA