At the end of September, the United Nations reinstated wide-ranging sanctions on Iran that had been suspended under the now-defunct JCPOA 2015 nuclear agreement. 

The move came after the three European signatories to the deal — Britain, France and Germany — triggered the so-called "snapback" mechanism embedded in the accord.

The renewed sanctions imposed a freeze on Iranian assets abroad, a halt on arms deals with Tehran and additional restrictions on Iran's ballistic missile program, among other measures.

"No big deal," Iranian Oil Minister Mohsen Paknejad remarked.

"In less than two years, 25 sanction packages with a total of 470 to 480 new punitive measures have been imposed on Iran. There are no further sanctions that could seriously concern us," he told reporters on October 1.

Maintaining pressure on Tehran

Some of the reinstated punitive measures are targeting Iran's nuclear program, in the aftermath of the US strikes on its nuclear sites which in June.  Following the 12-day war between Israel and Iran, which culminated with the US bombing Iran, US President Donald Trump claimed the nuclear sites were "obliterated."

Now, Washington wants to keep up the pressure on Tehran and force the theocratic regime to back down and completely give up its nuclear ambitions. In order to fund the nuclear program, Iranian elites are forced to pour enormous amounts of money into it — primarily through the revenue it generates by exporting crude oil.

"With the return of UN sanctions, restrictions now apply to Iranian shipping, there's a ban on the sale of fuel to Iranian tankers, increased inspections of ships carrying potentially dual-use goods, and restrictions on financial transfers," Dalga Khatinoglu, an expert on Iran's energy and economy, told DW. 

"This makes the legal export of Iranian oil considerably more difficult. Sales, transport and payment processing are severely restricted," he added.

Who benefits from the sanctions?

The Iranian regime has sought ways to circumvent international sanctions for years, including by building up a shadow financial and shipping network to facilitate oil trading.

At the end of July, the US government slapped new sanctions targeting more than 115 individuals, companies, and ships with ties to the Iranian oil industry. US Treasury Secretary Scott Bessent described it as the largest round of sanctions against Iran since 2018.

The restrictions primarily target the "elites of the regime" in Tehran, particularly a network of companies owned by Mohammad Hossein Shamkhani, the son of Ali Shamkhani, a close adviser to Supreme Leader Ayatollah Ali Khamenei.

The Shamkhani family has used its political influence to build up a shipping empire, controlling a large fleet of tankers and container ships that transport petroleum products from Iran and Russia, as well as other cargo around the world.

"The Shamkhani family's shipping empire highlights how the Iranian regime elites leverage their positions to accrue massive wealth and fund the regime's dangerous behavior," Bessent said in July.

But the Shamkhani family's shipping empire is not the only option for Iran to bypass sanctions.

The US has been able to uncover many of these networks in recent years due to "internal power struggles" in Iran, Hamzeh Safavi, a professor at the University of Tehran, said during a press conference with economic experts in Tehran earlier this week. "These networks expose each other in order to make billions in profits."

China pays for oil with infrastructure

"Just six months ago, Iran was selling its oil at a discount of around $1 compared to the Brent price," Homayoun Falakshahi, senior analyst at oil and commodities data company Kepler, told DW, referring to a global benchmark for oil prices.

"Three months ago, the discount was already $3, and now it's $6.5. Iran is currently offering its oil at discounts of $8 to $10 compared to similar grades from the Middle East," he added.

Despite sweeping US sanctions that make it nearly impossible to officially process financial payments to Iran, China continues to import Iranian oil.

The Asian giant, in fact, has been the largest buyer of Iranian oil since the US unilaterally withdrew from the 2015 nuclear agreement during President Trump's first term, in May 2018.

As reported by the Wall Street Journal on October 5, Iran and China have established a largely clandestine barter system, where Iranian oil is shipped to China, and in return, state-backed Chinese companies build infrastructure projects in Iran.

By circumventing the international banking system, this arrangement between the two sides has provided much-needed revenue to Iran, whose economy has been dealt a devastating blow by sanctions.

In 2024 alone, up to $8.4 billion (€7.2 billion) in oil payments flowed through this system to finance Chinese infrastructure projects in Iran, the US paper reported.

Additional reporting by Morad Rahmati.

This article was originally written in German.