On July 30, the US imposed new sanctions targeting a network of ships and international shipping companies related to Iran.
Washington accused the system of helping the Iranian government illegally transport tens of billions of dollars from oil exports.
The US Treasury Department said the sanctions target more than 100 individuals, companies and ships that Washington described as a huge shipping system run by trader Mohammad Hossein Shamkhani.
Mr. Mohammad is known to be the son of Mr. Ali Shamkhani - senior advisor to Iran's Supreme Leader Ayatollah Ali Khamenei.
According to the US officials, Mr. Mohammad took advantage of his father's influence to build a fleet of tankers and container ships, transporting large volumes of oil and products from Iran and Russia to customers around the world. These transactions are conducted through clearing companies to circumvent sanctions, launder money and conceal the origin of goods.
The US officials stressed that the new sanctions are part of a "maximum pressure" campaign resumed by President Donald Trump to maximize the benefits of the United States and end Iran's uranium enrichment program.
Responding to Washington's moves, Iran's Foreign Ministry on July 31 condemned the sanctions as illegal, saying that this reflected the US government's " systematic hostility" towards the Iranian people.
The West has long suspected Iran's uranium enrichment program as a stepping stone to develop nuclear weapons, despite Tehran repeatedly asserting that this is only part of the civil energy program.
Iran's leaders consider the uranium enrichment program a national pride, and have said they will not submit to any pressure or threat from the US and its allies.
