Commercial vessel traffic through the Strait of Hormuz rose on Thursday, but the strategic waterway remained caught between competing claims of access as Iran said it had closed the Strait and the US said it has total control.
The latest data from MarineTraffic show that 13 vessels crossed the Hormuz on Thursday, up 44% from nine a day earlier.
"Seven vessels entered the Middle East Gulf and six exited," the maritime data platform said in an X post on Friday.
Nine vessels used the Iran's Unilateral Scheme, while none were confirmed to have transited through the established Hormuz Traffic Separation Scheme, according to MarineTraffic data. Four vessels were categorized as route undetermined.
The increase in shipping comes amid reports of a tanker attack by an uncrewed aerial vehicle while conducting an outbound transit of Hormuz, according to the United Kingdom Maritime Trade Operations.
The UKMTO said the vessel sustained minor damage, while advising ships to exercise caution and report suspicious activity.
The UAE said late on Thursday that Iran attacked two vessels linked to state-owned energy giant Adnoc, which were transiting the Hormuz.
Iran's Islamic Revolutionary Guard Corps Navy commander, Rear Admiral Ali Ozmaei, reportedly said Friday that the Strait remained closed and that Iranian forces had complete and decisive control over vessel movements.
Ozmaei said that all movement in the strait was monitored by the IRGC Navy.
A spokesman for Iran's Central Khatam al-Anbia headquarters said no ship could safely pass without an Iranian permit and oversight, while rejecting US claims that vessels were normally transiting through the Strait.
Meanwhile, the US military said it had redirected 62 commercial vessels, disabled three and boarded two to enforce compliance with its blockade as of Aug. 14.
Traffic via Bab el-Mandeb rose to 29 crossings, up 4% from 28 the previous day, according to MarineTraffic. A total of 18 vessels entered the Red Sea and 11 exited. Two dark transits were recorded, while four sanctioned vessels and two shadow vessels were among the crossings.
Separately, two oil slicks have appeared in Iranian waters, as retaliatory attacks on oil tankers and other vessels by Iran and the US stoked concern about environmental damage to the Gulf, according to multiple media reports.
UK-based maritime risk and response firm Ambrey said it has been hired to salvage a grounded Russian shadow fleet tanker off Oman's coast and contain an oil spill that threatens wildlife.