Commodity ship traffic through the Strait of Hormuz has fallen to its lowest level since May following strikes involving U.S. forces and Iran’s Islamic Revolutionary Guard Corps, according to shipping data.

Analytics firm Kpler said the 10-day moving average declined to 10 vessel transits per day on Sunday. That compared with more than 15 on Friday and nearly 13 on Saturday. Only two ships passed through the strait on Saturday, followed by six on Sunday, with most using the Iranian route.

Context: Strait of Hormuz Intelligence File · Strait of Hormuz shipping guide · Strait of Hormuz

The drop followed a series of attacks on tankers and military vessels in and around the strategic waterway. U.S. Central Command said U.S. forces struck three Iranian oil tankers on Saturday, including one located off Kharg Island, Iran’s principal oil export hub. The action followed attacks by the IRGC on U.S. warships in the region.

Related context: Hormuz vessel traffic falls as tanker attacks heighten security concerns · Hormuz vessel transits fall as tanker attacks heighten security concerns · Middle East-China VLCC Earnings Approach $510,000 a Day · Commodity Vessel Transits Through Strait of Hormuz Fall to Three-Month Low

Operational context

The IRGC navy subsequently said it had targeted three oil tankers travelling on unauthorized routes through the strait, as well as three additional U.S. vessels elsewhere.

Maritime intelligence company Marisks identified the three Iranian tankers struck by U.S. forces as Downy, Stark I and Kylo, which is also known as Noxen. The company described Saturday’s attacks as a major escalation, warning that commercial tankers were increasingly being used as tools of reciprocal economic pressure.

Marisks assessed the risk as extreme for Iranian or Iran-linked tonnage and materially elevated for U.S.-linked or U.S.-escorted vessels operating across the Strait of Hormuz and the Gulf of Oman.

The United Kingdom Maritime Trade Operations said in its weekly report that 27 projectile strike incidents had been recorded since July 6, causing damage to vessels operating in and around the strait.

Limited traffic continued on Sunday. Kpler data showed that one very large crude carrier and three bulk carriers carrying metals, grains or oilseeds entered the waterway. Separately, LSEG data indicated that a tanker loaded with refined products at a Saudi port attempted to leave the strait but was turned back.

Kpler also reported that no VLCC had exited the Strait of Hormuz since Wednesday, underlining the disruption to large-scale crude movements through the route.