US troops moved into an area in which the new international boundary was disputed.
It became an international boundary with the independence of both countries from Yugoslavia in 1991.
It does become more complicated as you start crossing international boundaries.
It forms the international boundary between the two countries for much of its length.
It forms a part of the international boundary between the two countries.
It should be at least 200 miles from international boundaries and west of the Mississippi.
For much of its length it forms the international boundary between the two countries.
Flowing generally south, it forms the international boundary for around 6 miles.
He has had to cross three international boundaries in order to reach Chicago.
This is a global problem which has no regard for any international boundaries.