British Royal Marines seized the tanker last week off the coast of the British Mediterranean territory of Gibraltar on suspicion of violating sanctions against Syria.
Iran on Saturday reiterated its call for the ship’s release. It denies the tanker was taking oil to Syria in violation of European Union sanctions.
The affair has stoked tension in the Persian Gulf region, with Britain saying Thursday that it had fended off Iranian ships that tried to block a British tanker in the area.
Hunt said the call with Iran’s foreign minister had been constructive. He said Mohammad Javad Zarif had told him that Iran wanted to resolve the issue and was not seeking to escalate tensions.
“I reassured him our concern was destination not origin of the oil on Grace One & that UK would facilitate release if we received guarantees that it would not be going to Syria, following due process in [Gibraltar] courts,” Hunt wrote on Twitter.
A statement on the Iranian Foreign Ministry website said Zarif told Hunt during the call that Britain should quickly release the tanker.
Iran will continue its oil exports under any conditions, Zarif also told Hunt, according to the statement.
Tehran blames the United States for arranging the seizure of the tanker. Washington has imposed sanctions against Iran with the aim of halting Iranian oil exports.
European countries do not have sanctions against Iran, but have had them in place against Iran’s ally Syria since 2011. Gibraltar’s Chief Minister Fabian Picardo told the territory’s parliament on Friday that the decision to detain the tanker, which he said was carrying 2.1 million barrels of oil, had not been taken at the request of any other country.
“Also spoke to @FabianPicardo who is doing an excellent job co-ordinating issue and shares UK perspective on the way forward,” Hunt said.
Gibraltar police said four crew members who had been arrested, including the vessel’s captain and chief officer, were released on bail without charge, but that their investigation was ongoing.