Iranian Revolutionary Guard boats reportedly tried and failed to seize a British tanker as it sailed out of the Persian Gulf.

US Officials with direct knowledge of the incident said that five gunboats intercepted the tanker near the Strait of Hormuz and ordered the captain to sail towards Iranian territorial waters.  But the Iranians withdrew because a British warship warned them to back away.

"The Royal Navy HMS Montrose, which was also there, pointed its guns at the boats and warned them over radio, at which point they dispersed," one of the officials told the Reuters News Agency. 

"It was harassment and an attempt to interfere with the passage," said the other US official.

Britain's Ministry of Defence had no immediate comment.

This came less than a week after British Royal Marines stormed an Iranian ship that was suspected of carrying oil to Syria as it sailed near Gibraltar.