The United States said it destroyed three Iranian oil tankers on Saturday in response to attempted missile attacks on naval vessels, with Iran’s Revolutionary Guards saying they targeted US-linked ships in response.

The latest round of clashes, which began with US raids last week, comes amid a deadlock in the six-month war. Iran has maintained its stranglehold on the strategic Strait of Hormuz as Washington continues pressing its counter-blockade of Iranian ports.

In addition to the renewed military action, Washington is also seeking to choke Iran’s economy, announcing sanctions on entities with financial links to the Islamic republic in a bid to force it into submission.