Islamic Republic of Iran Navy
It is charged with the responsibility of forming Iran's first line of defense in the Gulf of Oman and beyond with the mission of acting as an effective blue-water navy. However, it is generally considered as a conventional green-water navy as it mostly operates at a regional level, in the Persian Gulf and Gulf of Oman but also as far afield as the Red Sea, the Mediterranean Sea and northwest quarter of the Indian Ocean. In July 2016, the Navy said that it would establish a presence in the Atlantic Ocean, of unspecified duration.
2008 U.S.–Iranian naval dispute
To travel through the Strait of Hormuz, which at its narrowest is wide, ships pass through the territorial waters of Iran and Oman under the "transit passage" provisions of the United Nations Convention on the Law of the Sea. Neither Iran or the United States have ratified the convention, but the United States accepts the traditional navigation rules as reflected in the Convention. Iran has stated that it reserves "the right to require prior authorization for warships to exercise the right of innocent passage through its territorial sea." It is unclear if the incident happened in the territorial waters of Iran or Oman.