When countries share a border it is referred to as a "common or shared" border.
they have common sea
egypt
countries except iran,afghanistan,india and china dont share the common border with pakistan....!
France and Portugal
Yes, the two countries have a common border.
They produce oil.
They all have oil resources
Yes, "southern border" is a common noun. It refers to a physical or imaginary line that separates two areas, regions, or countries.
Both countries share a common border.
The two countries share a common border.
They are trading blocs with countries as members.