ISTANBUL

US officials said Thursday that Iran has begun laying mines in the Strait of Hormuz, in a move that could disrupt global shipping, the New York Times reported.

After US forces destroyed larger Iranian vessels capable of quickly laying mines, Iran began using smaller boats for the operation, according to a US official briefed on the intelligence.

Iran’s Islamic Revolutionary Guard Corps can deploy hundreds of these boats, which it has long used to harass larger ships, including those of the US Navy, said the outlet.

US officials said the new mining effort is slow and not highly efficient, but Iran appears to be aiming to deploy mines faster than they can be cleared, hoping to further deter shipping through the strait, a vital waterway through which about 20% of the world's crude oil and natural gas typically passes.

Iran announced that the strait was closed after the US and Israel launched joint attacks on Feb. 28, disrupting shipping and raising oil prices.

Strikes have hit multiple vessels in the area since, some of which Iran claimed responsibility for.

On Tuesday, Iranian Deputy Foreign Minister Majid Takht-Ravanchi denied that Iran was mining the strait.

In his first statement since the conflict began, Iran’s new supreme leader, Mojtaba Khamenei, said Thursday that the “lever of blocking the Strait of Hormuz must continue to be used.”

The US military has targeted 16 Iranian mine-laying ships, while US President Donald Trump warned Iran that it would face severe consequences if it blocked oil flows, media reported.

Mines in the region have historically damaged shipping, and with roughly one-fifth of the world's oil consumption and LNG trade passing through the Strait, Iranian activity remains a key concern for the US military and intelligence agencies, according to the outlet.