LONDON — The British and Gibraltar authorities will soon release an Iranian oil tanker that has been held for more than a month, an Iranian official said on Tuesday, signaling a possible step toward de-escalating tensions between Tehran and the West that threaten world energy supplies.
Officials in Gibraltar and London would not confirm or deny the Iranian claim about the impending release of the tanker, the Grace 1, which was seized on July 4 off the coast of Gibraltar.
Jalil Eslami, the deputy head of Iran’s maritime agency, predicted the release at a news conference, and his remarks were reported by several Iranian news organizations with ties to the government.
“We believe that Grace 1 oil tanker will resume operation under Iranian flag in international waters in the very near future,” Mr. Eslami said, according to the Fars news agency. PressTV quoted him as saying, “Certain documents have been exchanged, which would help settle the issue.”
Britain’s Foreign Office said it had no immediate response. The government of Gibraltar, a semiautonomous British territory, declined to comment beyond a one-sentence statement: “We continue to seek to de-escalate issues arising since the lawful detention of Grace 1.”
Iran seized a British tanker, the Stena Impero, last month in the Strait of Hormuz, and officials have hinted since then at the possibility of a trade. Iran has also seized a tanker registered in Panama and chartered by a company in the United Arab Emirates, and it has said that it took an Iraqi tanker, too.
The tanker seizures, United States sanctions intended to cut off Iran’s ability to sell oil, and recent attacks on tankers near the strait that American officials have attributed to Iran have ramped up friction. About 20 percent of the world’s oil supply flows through the strait.
The tensions are rooted, in large part, in disagreements about Iran’s nuclear program and the 2015 agreement that restricted it. European countries have warned against allowing the conflict to escalate into warfare.
The Gibraltar authorities said they had seized the Iranian tanker, with the help of British marines, because it was taking oil to Syria in violation of European Union sanctions. Jeremy Hunt, who was the British foreign secretary when the ship was seized last month, had said that the Grace 1 could be returned if Britain received assurances that it would not go to Syria.
Despite the attempts to frame the seizure as separate from the dispute between Iran and the West, Tehran described the action as illegal and accused Britain of acting at the behest of the Trump administration.
Iranian officials called the July 20 seizure of the British tanker Stena Impero a “reciprocal action.”
In May 2018, President Trump withdrew the United States from the nuclear deal and reimposed sanctions that the agreement had suspended. Almost a year later, he imposed a new set of sanctions, trying to cut off Iranian oil sales, and the attacks on tanker traffic began soon after.