Iranian forces reportedly tried to stop and divert a British oil tanker as it crossed into the Strait of Hormuz on Wednesday, the UK said, but they were warned off by a British naval vessel.
Three Iranian boats ordered the vessel to change course, a UK government statement said.
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“Contrary to international law, three Iranian vessels attempted to impede the passage of a commercial vessel, British Heritage, through the Strait of Hormuz,” the statement said.
The Iranian vessels only turned away after the UK naval frigate HMS Montrose intervened, positioning itself between the tanker and the Iranian vessels and warning them to back off.
“We are concerned by this action and continue to urge the Iranian authorities to deescalate the situation in the region,” said the UK statement.
The Iranian Revolutionary Guard, which patrols the waters, denied that any incident had taken place. “In the last 24 hours, we had no incident involving foreign vessels in the Strait of Hormuz, also not with a British one,” a statement said.
The vessel, which was leaving the Persian Gulf at the time of the reported incident, was on Thursday seen to have passed the Strait of Hormuz and was passing through the Gulf of Oman.
Russia urged restraint, saying that it was aware of both Britain’s statement on the incident and Iran’s denial. Kremlin spokesman Dmitry Peskov said “freedom of navigation should be ensured in the Persian Gulf and the Strait of Hormuz.”
Warning of consequences
Iranian President Hassan Rouhani on Wednesday had warned Britain of unspecified “consequences” over the detention of an Iranian oil tanker last week off the British overseas territory of Gibraltar.
The Grace 1 tanker was halted by British police and customs officers on its way from Iran to Syria, via the Mediterranean.
While officials in Gibraltar said they believed the cargo was destined for Syria, which is subject to EU sanctions, Iran condemned the detention as an “illegal interception.”
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The crude oil was said to be on its way to the Baniyas oil refinery, which is controlled by the Syrian government. Iran-backed Hezbollah has been an ally of President Bashar Assad’s regime throughout the Syrian civil war.
As Rouhani made his comments on Wednesday, ahead of the latest incidents, he mocked the UK as “scared” and “hopeless” for using the Royal Navy to shadow vessels on their way through the Strait of Hormuz.
Tensions around the Strait of Hormuz have heightened significantly since the US stepped up economic sanctions against Tehran, moving to bring the country’s oil exports to zero.
Coalition to safeguard seas
Under a plan announced on Tuesday, the US has called on allies to join it in a coalitionthat would patrol waters off Yemen.
Under the plan, the US would provide “maritime domain awareness and surveillance,” while each coalition member would provide protection to the commercial vessels that fly under its flag.
Read more: Iran-US tensions flare in the Persian Gulf: What’s at stake?
Patrols would be carried out in particularly vulnerable waterways such as the Strait of Hormuz, between the Persian Gulf and the Gulf of Oman. The Bab el Mandeb, which separates Yemen from the Horn of Africa, would also be included.
The US last year withdrew from the 2015 nuclear deal with Iran, known as the Joint Comprehensive Plan of Action (JCPOA). Washington has since sought to influence European signatories, as well as Russia and China, to turn their backs on the deal.
