Ship-tracking data from the Kpler institute shows that on Sunday only six vessels transited the Strait of Hormuz, the lowest figure in the past five weeks.

The drop in traffic occurred as the tit-for-tat attacks between the United States and the Islamic Republic intensified.

The Islamic Revolutionary Guard Corps says it has closed the strait until further notice; a claim that U.S. Central Command rejects, saying traffic is ongoing and that the southern route remains open via waters off Oman.

Two weeks ago on Wednesday, 76 ships had passed through this waterway. Before the war, about 120 ships transited the Strait of Hormuz per day.