An oil slick from a grounded sanctioned tanker off Oman has spread across about 400 square kilometres, according to reports.

The vessel, Caroline Bezengi, has grounded near the the Al Hallaniyat Islands in Dhofar Governorate, Oman’s Environment Authority said in a statement on Friday.

The UK government has put the tanker under sanction list for links to the Russian shadow fleet.

According to the Oman News Agency, the oil slick covers about 390 square kilometres (150 square miles).

The vessel was carrying Russian oil bound for Asia and first reported damage on June 8 off Yemen, Reuters reported yesterday.

Meanwhile, environmental group Greenpeace said on August 5 that satellite imagery analysis showed the slick had spread to about 600 square kilometres.