Tehran has condemned the first round of US sanctions targeting individuals and companies accused of facilitating Iranian oil sales, calling the move illegal and unjustified.

“The Islamic Republic of Iran holds the United States accountable for the consequences and repercussions of such unilateral and bullying actions,” Foreign Ministry spokesperson Esmail Baghaei told Iranian media on Friday.

This comes after Washington imposed new sanctions on networks facilitating Iranian oil shipments to China, a move aligned with US President Donald Trump's decision to revive his "maximum pressure" campaign on Tehran.

The sanctions, officially announced by the Treasury Department, target companies and vessels across China, India, and the UAE.

“The decision of the new US administration to exert pressure on the Iranian nation by preventing Iran's legal trade with its economic partners is an illegitimate, unlawful, and wrongful act that entails international responsibility for the US government,” Baghaei said.

The US says Iran funnels billions of dollars of oil revenue into its nuclear program, missile development, and regional militant groups -- including, US-designated terrorist entities Hamas, the Houthis, and Hezbollah.

“The United States is committed to aggressively targeting any attempt by Iran to secure funding for these malign activities,” Treasury Secretary Scott Bessent noted in his statement on Thursday.

During President Trump's first term in office, Tehran's oil exports were reduced to near zero by re-imposing sanctions. Under former US President Joe Biden Iran's oil exports increased starting in 2021 as Tehran found ways to circumvent those sanctions.