Britain may release tanker if Iran 'guarantees' oil isn't going to Syria

July 13 (UPI) -- The British foreign secretary said the Iranian tanker detailed near Gibraltar could be released in exchange for a guarantee that the oil would not be taken to Syria.

Foreign Secretary Jeremy Hunt tweeted Saturday that he had a "constructive call" with Iranian Foreign Minister Javad Zarif about the tanker, which was seized by Royal Marines July 4 on suspicion of breaching sanctions imposed by the European Union.

Hunt said he reassured Zarif that Britain's concern is about the "destination" rather than the "origin of the oil" aboard the tanker Grace 1.

He said the tanker could be released "if [Britain] received sufficient guarantees that it would not be going to Syria."

Hunt said Zarif assured him "that Iran wants to resolve [the] issue and is not seeking to escalate."

Grace 1 was seized by a team of Royal Marines that the British government says were summoned to help detain the tanker at the request of the Gibraltar government. Authorities said the tanker was suspected to be carrying crude oil to the Baniyas Refinery in Syria, which would violate EU sanctions against Syria.

Iran denied the tanker had been bound for Syria and warned of retaliation if the tanker was not released. Five Iranian military gunboats attempted to detain a British oil tanker in the Persian Gulf on Wednesday.

The gunboats disengaged when British warship HMS Montrose, which was less than five miles behind the tanker, threatened to open fire.