The UK government has said it is “deeply concerned” about Iran’s “unacceptable” seizure of a British-flagged tanker in the Gulf.
The Stena Impero’s owners say they have been unable to contact the ship, which was seized in the Strait of Hormuz, a key waterway in the region.
Foreign Secretary Jeremy Hunt has warned of “serious consequences” if the situation is not resolved quickly.
Iran said the ship was “violating international maritime rules”.
The Stena Impero was seized on Friday by the Iranian Revolutionary Guard, according to the semi-official Fars news agency.
Stena Bulk, which owns the vessel, said it was in “full compliance with all navigation and international regulations” and was approached while it was in international waters.
Mr. Hunt said the tanker had been surrounded by four vessels and a helicopter and was heading into Iranian waters.
There were no reported injuries among the 23 crew members, who are Indian, Russian, Latvian and Filipino, Stena Bulk said.
A second British-owned Liberian-flagged tanker, the MV Mesdar, was also boarded by armed guards but was released.
Its Glasgow-based operator, Norbulk Shipping UK, said communication had been re-established with the vessel and its crew was “safe and well”.
A White House National Security Council spokesman said this latest incident was the second time in just over a week the UK had been “the target of escalatory violence” by Iran.
Iran has been blamed by the US for attacks on tankers which have happened in the world’s key shipping area since May. Tehran denies all the accusations.
Tensions between the US and Iran have risen sharply since the US tightened sanctions it reimposed on Iran after unilaterally withdrawing from a landmark 2015 nuclear deal.
On Friday, the US claimed to have destroyed an Iranian drone in the Gulf.
Source: BBC News