China, one of Iran’s largest oil buyers, relies heavily on discounted Iranian crude, much of it processed by smaller independent “teapot” refineries concentrated in eastern provinces such as Shandong.

The Chinese commerce ministry said U.S. sanctions targeting the firms, announced separately since last year, “shall not be recognized, implemented, or complied with,” describing the restrictions as unilateral measures lacking legal legitimacy.

The ministry said the sanctions “improperly prohibit or restrict Chinese enterprises from conducting normal economic, trade and related activities with third countries” and argued they violated international law and the basic norms governing international relations.“The Chinese government has consistently opposed unilateral sanctions lacking U.N. authorization and a basis in international law,” the ministry said in a statement.

The injunction applies to three companies based in Shandong province Shandong Jincheng Petrochemical Group, Shandong Shouguang Luqing Petrochemical and Shandong Shengxing Chemical along with Hengli Petrochemical (Dalian) Refinery and Hebei Xinhai Chemical Group.

Washington has intensified efforts to curb Iran’s oil revenues, which it says help finance Tehran’s regional activities and strategic programs, by expanding sanctions on Chinese refiners and shipping entities involved in the trade.

On Friday, the United States imposed sanctions on another Chinese company, Qingdao Haiye Oil Terminal Co. Ltd., alleging it had imported “tens of millions of barrels” of Iranian crude worth billions of dollars for Tehran.That company was not included in Beijing’s latest formal injunction.

The dispute comes as U.S.-Iran tensions remain high following the conflict triggered by U.S.-Israeli strikes on Iran in late February, with diplomatic efforts failing so far to produce a lasting resolution.Energy flows through the Gulf and the Strait of Hormuz remain under close international scrutiny as sanctions pressure and military tensions continue to shape global oil markets.

The sanctions dispute also adds another layer of complexity ahead of U.S. President Donald Trump’s expected visit to China later this month, where talks with Chinese President Xi Jinping are likely to include trade disputes, regional security and Iran-related tensions.

China’s foreign ministry spokesman Lin Jian said Washington should “speak and act cautiously” on Taiwan and “correct their understanding of China,” responding to questions about the U.S. report during a regular press briefing in Beijing.

Lin reiterated Beijing’s position on Taiwan, which it considers part of its territory, and called on the United States to avoid actions or rhetoric that could escalate tensions. The Taiwan issue remains one of the most contentious points in U.S.-China relations, with Washington maintaining unofficial ties and providing defensive support to the self-ruled island.

The U.S. intelligence report, referenced in the exchange, assessed that China does not have plans to launch an invasion of Taiwan in the coming year, offering a near-term outlook that contrasts with broader concerns in Washington over Beijing’s long-term military intentions.

The remarks underscore ongoing friction between the world’s two largest economies over security perceptions and strategic competition. U.S. officials have repeatedly warned about China’s growing military capabilities and assertiveness in the Indo-Pacific, while Beijing has accused Washington of exaggerating threats to justify its regional posture.

Lin said the United States should align its statements and actions more carefully on Taiwan, signaling Beijing’s continued sensitivity to external commentary on the matter.

China’s response reflects its consistent opposition to what it describes as the “China threat theory,” a narrative Beijing says mischaracterizes its intentions. Lin said the United States should align its statements with what China views as a more accurate understanding of its policies.

The exchange highlights the sensitivity surrounding Taiwan, which remains a central point of contention in relations between China and the United States, particularly in the context of security assessments and diplomatic signaling.

Public statements tied to intelligence findings often carry broader geopolitical implications, shaping perceptions among regional actors and influencing diplomatic engagement.

The latest comments underscore how both sides continue to manage competing narratives while maintaining firm positions on sovereignty and security concerns.