Saudi Arabia and Oman
Yemen, Somalia, and Djibouti border the Gulf of Aden.
A border separating two countries is called an international border or a national border.
Yemen shares its borders with Saudi Arabia and Oman. Its coastline lies along the Red Sea and the Gulf of Aden.
Do you mean countries? If you do, the two countries that border the U.S. are Canada and Mexico.
Yemen and Oman are at the southern end of the Arabian Peninsula.
Yemen and Oman border Saudi Arabia to the south.
Yemen, Somalia, and Djibouti border the Gulf of Aden.
Egypt and Yemen.
Oman and Iran are the only countries that border the Gulf of Oman.
yemen
Yemen was two countries until 1990.
Yemen and Oman.
If the Gulf of Aden where in the center then Yemen, Djibouti, Somalia, and the Indian Ocean border the Gulf (with Yemen to the North, working counter-clockwise)
Directly north of Yemen is Saudi Arabia. The two countries share a long border that runs along the Arabian Peninsula. Saudi Arabia is one of Yemen's closest neighbors and has significant political and economic interactions with Yemen.
Egypt, Sudan, Soudi Arabia and Yemen
Yemen was two countries until 1990.
Yemen