The United States and Iran have been trading waves of attacks, as a dispute over control of the Strait of Hormuz threatens to derail efforts to end their war.

BBC correspondent Barbara Plett Usher, reporting from Jerusalem, examines the latest tensions over the key international shipping channel.

Over the weekend, Iran announced that the strait was closed, while the United States insisted that it was not controlled by Iran and that traffic was flowing.

The escalation has cast doubt on the preliminary agreement the United States and Iran signed in June to end their four-month conflict and reopen the strait.