A Bermudian-based oil tanker operator today revealed three of its ships were moving freely again after being stranded for months during hostilities in the Middle East.

Herbjorn Hansson, chairman and chief executive officer of Nordic American Tankers, said: “We have had three ships stuck in the Arabian Gulf. The problems started February 28 this year.

“These vessels have now gone through the Hormuz Strait and are again involved in international business. Our crews are safe.”

Nordic American, which was incorporated in Bermuda in 1995, has a fleet of Suezmax tankers. Mr Hansson added that the company continued to experience “excellent market conditions”.

The news came as Bloomberg News reported today that a ship-tracking service showed four Saudi-owned supertankers, hauling crude loaded at Saudi Arabia’s main export hub, appeared in the Gulf of Oman today - the largest number of exits from the Strait of Hormuz since the peace pact came into effect about two weeks ago.

Traffic through Hormuz has picked up, the report added, with ships increasingly moving in convoys to clear the strait. Vessels are generally passing through a US-administered corridor in Omani waters, though some are using a route closer to Iran's coast.

However, the Associated Press reported that Iran’s joint military command warned today that all oil tankers moving through the Strait of Hormuz must use its approved routes or face a “forceful response”, again ratcheting up tensions over a waterway crucial for international energy supplies.

Gavin Maguire, a Reuters columnist, said this week that laden export flows out of the Strait remained “constrained”.

“Hundreds of vessels remain stuck in or around the Gulf, creating a bottleneck that could take weeks to fully unwind even under stable conditions,” Mr Maguire added.