The Suez Canal’s international status has a murky history. Per the 1888 Convention of Constantinople, the canal is open to ships of all nations in peacetime and wartime. However, there have been numerous instances of ships being denied passage in wartime, especially during World War I and World War II. Because of tensions with Israel, Egypt closed the canal during the Suez Crisis of 1956–57 and the Arab-Israeli War of 1967.