By Jonathan Saul
LONDON, June 15 (Reuters) - Ensuring the Strait of Hormuz is safe from mines could delay a return to normal shipping traffic by weeks following a deal to reopen the waterway, shipping and maritime security sources say.
The operation by conventional minesweepers and state-of-the-art underwater drones could continue for 40 to 50 days before many insurance, shipping or oil companies are confident enough to sail through, according to assessments from five Western maritime security sources.
That could potentially hold up tens of millions of barrels of oil, in addition to the oil supply from the Gulf already blocked since the United States and Israel attacked Iran on February 28, according to estimates based on pre-war flows.
Every export barrel from the Gulf is crucial given stockpiles in the world's largest economies are headed toward their lowest levels since at least 2003, according to analysis last week by the U.S. Energy Information Administration.
Even though Iran and the U.S. quietly helped ships pass through the blockaded waterway in recent weeks, shipping officials continued to urge caution after the U.S. and Iran said on Sunday they had reached a preliminary agreement to end their war and reopen the strait.
"We still consider it very risky for ships to commence transits at this point," said Jakob Larsen, chief safety & security officer at shipping association BIMCO.
"The threat of mines in the area remains a concern immediately as well as further down the line and mine-free routes need to be established."
ASSURANCES SOUGHT BY SHIPPERS
It is unclear how many mines Iran may have laid in the strait, which handled 20% of the world's daily supply of oil and liquefied natural gas before the war.
Iran, which has sought to assert its control over the waterway during the war, has threatened to deploy naval mines, without commenting on whether its forces have planted them.
The U.S. has indicated that mines are a risk, and says it has targeted Iranian mine-laying boats.
On June 2, U.S. Secretary of State Marco Rubio told a Senate Foreign Relations Committee hearing that Iran had "mined large segments of Hormuz — international waters", without elaborating.
In a June 11 note, Germany's navy, citing information from the U.S. and British navies, said mines were located in four locations around the strait, adding that the mine locations could not be verified by Germany.
Even the possibility of mines could deter companies. A supertanker and its cargo of crude are worth about $300 million, so war risk underwriters, oil and tanker companies would need assurances that passage is safe before they attempt to pass through the strait, shipping industry officials said.
"One sea mine is enough to have fatalities," said Rene Kofod-Olsen, CEO of V.Group, one of the world's top technical ship and crew management specialists which has 13 ships stuck in the Gulf.
"That's obviously a massive issue for global shipping," he said.
SHIPPING TRAFFIC REMAINED LOW
When asked last week about how many mines had been laid and locations, a spokesperson with the U.S. military's Central Command (Centcom) said it was unable to publicly discuss specifics for operational security reasons.
"U.S. military efforts for ensuring the Strait of Hormuz is fully clear of sea mines laid by Iran’s Islamic Revolutionary Guard Corps are ongoing," they said.
The White House did not respond to requests for comment.
Oman’s Maritime Security Centre warned mariners on May 30 navigating around its side of the strait to exercise caution after it described the sighting of an "object suspected to be a floating mine".
Oman's information ministry did not immediately respond to a request for comment.
As Iran and the U.S. negotiated over the interim deal to halt the war, both sides enabled some ships to exit the strait.
U.S. President Donald Trump said last week that the U.S. had been taking millions of barrels of oil out, and Reuters reported in May on how some states have struck deals with Tehran to secure passage for vessels.
The number of ships passing through the strait increased to an average of 12 to 15 vessels a day in recent weeks, according to shipping data that can be verified once the vessels become visible after leaving the strait. But that is a fraction of the 120 to 140 ships that passed through the waterway daily before the war.
THREAT OF MINES
In March, before the agreement of a tenuous ceasefire between the U.S. and Iran, Iran's National Defence Council said any attempt by "the enemy" to target Iranian coasts or islands would lead to mining of access routes and communication lines throughout the Gulf, according to Iran's semi-official Fars news agency.
It said measures would include various types of naval mines, including floating mines that could be launched from shore.
Iran's foreign ministry did not respond to a request for comment.
Britain, France and Germany have all despatched warships and minesweepers to the Middle East in anticipation of a potential mine clearing operation.
Corey Ranslem, chief executive of maritime security group Dryad Global, said even after U.S. strikes aimed at destroying Iranian military capacity including mine laying vessels and stocks, Iran was estimated to possess up to 1,000 naval mines.
"If there is a mine field detected, it could potentially take weeks or months to remove the threat," he said.
Arsenio Dominguez, head of the U.N.'s shipping agency, on Monday welcomed the deal to reopen Hormuz as "an important step toward restoring safety in this vital maritime corridor for seafarers and ships".
"However, its implementation will require time to ensure that all necessary safety and security guarantees are in place," he said.
(Reporting by Jonathan Saul and Sabine Siebold, additional reporting by Michel Rose, John Irish, Renee Maltezou, Parisa Hafezi and Andrew Mills, editing by Rachel Armstrong and Aidan Lewis)
