A map showing an approximate route of the Grace 1 tanker, which authorities in Gibraltar say was headed for Syria.

  • An Iranian oil tanker seized in the Mediterranean on Thursday took a very unusual route, going the whole way round Africa rather than using the Suez Canal.
  • It was seized off Gibraltar, where authorities say the tanker, called the Grace 1, was carrying Iranian oil to Syria in violation of EU sanctions.
  • According to an intelligence source cited by Reuters, the route - which is more than 16,000km, could be an attempt to avoid being caught in the Suez Canal, where security is greater.

An Iranian tanker seized by British authorities took detour around Africa of around 22,000km, in what could be an attempt to avoid scrutiny and sneak thousands of tonnes of crude oil to Syria.

Authorities in Gibraltar, a British territory, seized the Grace 1 tanker on Thursday, saying they believe it was bringing government-owned oil refinery in Syria, an act that violates EU sanctions.

According to Reuters and The Associated Press, tracking data showed that the ship took a very unusual route to the Mediterranean.

It began in Iran, then travelled all the way around Africa on its way to Syria. Had it not been seized near Spain, the journey would have been around 22,000km, according to shipping route website Sea Distances.

The much more ordinary route for such a journey would be via the Suez Canal in Egypt, which links the Red Sea and the Mediterranean.

That journey would have been just over 6,000km, according to Sea Distances, potentially saving the Grace 1 an extra 16,000km round Africa.

The Grace 1 oil tanker, seen off Gibraltar on July 4 after being boarded by the Royal Marines.

The route around Africa would also have taken almost 33 days, compared to nine days to travel via Suez Canal, Sea Distances calculated.

The distances involved are rough, as Business Insider does not have access to precise location data for the vessel.

A likely reason for the odd route could be the lesser chance of being caught going the long way round.

A maritime intelligence source told Reuters that the ship may have avoided the Suez Canal because that route involved unloading its cargo, where it would run the risk of being caught and seized.

This is what this route would have looked like:

The journey through the Suez Canal would have been much shorter.

The EU has banned oil shipments to Syria since 2011 as part of sanctions over President Bashar Assad's treatment of civilians.

Iran claims that its ship has been illegally detained, and summoned the UK ambassador. The UK central government and the US praised Gibraltar's action.

Reuters reported that it had seen shipping data that suggested the ship was loaded with oil in Iran, though the ship's documents say it was loaded in Iraq.

The ship was seized in Gibraltar — far from Iran and Syria.

The ship was recently tracked in Iran's Bandar Assalyeh port, according to Reuters.

An analyst at Kpler, a London-based energy data firm, told Reuters that the ship loaded Iranian crude oil at Iran's Kharg Island port in mid-April.

Spain's caretaker foreign minister said that the tanker was stopped at the request of the US, which has seen tensions increase with Iran in recent weeks as it tightens sanctions around Iran's oil exports.