The U.S. on Oct. 26 imposed fresh Iran-related sanctions targeting the Islamic Republic's oil sector, including the Iranian Ministry of Petroleum, in Washington's latest action to increase pressure on Tehran.

The U.S. Treasury Department in a statement said it was slapping sanctions on key actors in Iran's oil sector for supporting the Quds Force, the elite foreign paramilitary and espionage arm of the Islamic Revolutionary Guard Corps blacklisted by the United States.

"The regime in Iran uses the petroleum sector to fund the destabilizing activities of the IRGC-QF," Treasury Secretary Steven Mnuchin said in the statement.

The minister of petroleum, the National Iranian Oil Co. (NIOC) and National Iranian Tanker Co. were also blacklisted alongside other individuals and entities in Washington's move on Oct. 26, which freezes any U.S. assets of those blacklisted and generally bars Americans from dealing with them.

The action imposes counterterrorism sanctions on NIOC, the National Iranian Tanker Co. and National Petrochemical Co., which had previously been blacklisted by Washington under different authorities.

Tensions between Washington and Tehran have soared since President Donald Trump unilaterally withdrew in 2018 from the Iran nuclear deal struck by President Barack Obama and began reimposing U.S. sanctions that had been eased under the accord.

Iranian oil exports rose sharply in September in defiance of U.S. sanctions, according to three assessments based on tanker tracking, throwing a lifeline to the Islamic Republic and its collapsing economy.

Exports have shrunk from over 2.5 million bbl/d since the U.S. withdrew from the nuclear deal. Still, Iran has been working to get around the measures and keep exports flowing.

"The few remaining buyers of Iranian crude oil should know that they are helping to fund Iran’s malign activity across the Middle East, including its support for terrorism," U.S. Secretary of State Mike Pompeo said in a separate statement.

The Treasury also imposed sanctions on Mahmoud Madanipour and United Arab Emirates-based Mobin International Ltd., accusing them of entering into an agreement with Venezuelan state-owned Petroleos de Venezuela (PDVSA) to ship gasoline obtained from NIOC to the government of Venezuelan President Nicolas Maduro.

The British-based companies Madanipour, Mobin Holding Ltd. and Oman Fuel Trading Ltd. were also blacklisted.

Mobin International and Oman Fuel have said they were the owners of the cargo aboard several tankers confiscated by U.S. authorities in August.

The U.S. Justice Department said the cargo was destined for Venezuela, whose oil industry is also under U.S. sanctions, but the companies denied in court filings that Venezuela was the destination.