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The United States is imposing sanctions on Iran's petrochemical industry — the country's second-largest source of revenue — in a bid to cut off funds that the Islamic republic might use for developing its nuclear program, the U.S. Treasury Department announced last week.

Eight companies have been blacklisted by the Treasury Department. They are Bandar Imam Petrochemical Company, Bou Ali Sina Petrochemical Company, Mobin Petrochemical Company, Nouri Petrochemical Company, Pars Petrochemical Company, Shahid Tondgooyan Petrochemical Company, Shazand Petrochemical Company and Tabriz Petrochemical Company, all of which are either owned or controlled by the Iranian government. The list also mentioned companies based in Kyrgyzstan, Ukraine and the United Arab Emirates, claiming that they leased aircraft used by Iran to ship "illicit cargo" to help the Syrian regime fight its opposition.

The sanctions were imposed despite Iran's claims that its nuclear program was strictly intended for civil purposes. Two more companies, Jam Petrochemical Company and Niksima Food and Beverage JLT, were sanctioned by the U.S. State Department for taking part in "the purchase or acquisition of petrochemical products from Iran," it was also announced. Jam Petrochemical Company is based in Iran and is a producer and seller of petrochemicals. The second company, Niksima Food and Beverage JLT, was found to have received payments on behalf of Jam Petrochemical Company, the State Department said. Jen Psaki, spokeswoman for the State Department, explained that both companies are not allowed to make any financial transactions related to property and interests in property under U.S. jurisdiction and foreign exchange transactions subject to U.S. jurisdiction. Meanwhile, another company, Ferland Co., based in Cyprus and Ukraine, was sanctioned over its attempts to hide oil transactions with the government of Iran.

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According to the U.S. Treasury Department, the Iranian government has tried to turn to other industries to make up for lost profits, following declining oil revenues amid international oil sanctions. One of the key sectors and one of the industries that the Iranian government had planned to use was the petrochemical industry. This forced the United States to impose new sanctions on Iran, this time affecting some of its biggest petrochemical companies, the statement said.

The Treasury Department added that it was committed to intensify sanctions against Iran, not only by adopting new ones, but also by making sure that sanctions are properly enforced and sanctions evasion is efficiently prevented. The latest actions regarding the Iranian petrochemical industry target revenues from Iran's second-most lucrative sector, as well as potential deceptive schemes that the country may have been engaged in, trying evade sanctions on its oil sales and its airlines. Treasury under secretary for terrorism and financial intelligence David S. Cohen stated that the United States would continue its cooperation with international partners around the world to ensure that the sanctions pressure on Iran in increased, for as long as Iran continues to refuse to comply with its international obligations.