(BSS/AFP) - The United States announced Wednesday it is tightening sanctions against Iran`s oil industry as Tehran keeps up its closure of the Strait of Hormuz as part of the Mideast war.

The new punishment targets oil transport infrastructure by slapping sanctions on more than two dozen people, companies and ships that operate within the network of petroleum shipping magnate Mohammad Hossein Shamkhani, the Treasury Department said.

"Treasury is moving aggressively with `Economic Fury` by targeting regime elites like the Shamkhani family that attempt to profit at the expense of the Iranian people," US Treasury Secretary Scott Bessent said in a statement, alluding to a financial pressure campaign against Iran.

Shamkhani is the son of security official Ali Shamkhani, an advisor to Iranian supreme leader Ali Khamenei, both of whom were killed February 28, the first day of US-Israeli attacks and the start of the Middle East war.

"The United States is acting to decisively limit Iran`s ability to generate revenue as it attempts to hold the Strait of Hormuz hostage," the State Department said in a separate communique.

Iran has effectively shut down the Strait of Hormuz, a key conduit for shipping oil and gas, in retaliation for the US and Israeli war campaign.

The United States is now engaged in a naval blockade of Iran`s ports.

On Tuesday, the Treasury Department said it would not extend a temporary sanctions waiver that allowed the sale of Iranian oil already at sea. This had been an attempt to ease pressure on oil prices that shot up because of the war.

The United States alleges that the Shamkhani network, which operates in Iran and the United Arab Emirates, dodges sanctions through a group of seemingly legitimate consulting and shipping companies that run the network`s fleet.

Last year the United States imposed sanctions against entities linked to the network.

The Treasury Department also announced Wednesday it was imposing sanctions against an Iranian man named Seyed Naiemaei Badroddin Moosavi, whom it described as a financier for the Iran-backed militant group Hezbollah, and "three companies linked to a complex money laundering scheme involving the sale of Iranian oil in exchange for Venezuelan gold."