China criticizes US threat of sanctions on Iran and trading partners

China has criticized the US threat of sanctions on Iran and its trading partners, with Foreign Ministry spokesman Lin Jian saying Beijing opposes unilateral sanctions that have no basis in international law.

Lin said in Beijing on Tuesday that an economic war would not lead to a solution but would instead escalate conflicts and disrupt the global financial order.

Beijing called for de-escalation and a return to dialogue. Lin said China would take all necessary measures to protect its interests.

The US had previously threatened action against Iran's trading partners.

Treasury Secretary Scott Bessent said on Monday that the US Treasury had "mapped every node, every facilitator and every network that Iran has used to smuggle oil and evade sanctions."

China is the world's largest buyer of Iranian oil. Lin said in response to a question that cooperation between China and Iran was conducted within the framework of international law and should not be disrupted.

Some of the measures target several companies based in the Chinese special administrative region of Hong Kong, as well as other individuals in China, according to the US Treasury statement.

The US aims to disrupt Iran's global procurement network for nuclear and missile technology. The companies are said to have acted as intermediaries in procuring key goods for Iran, including optical technical equipment, the statement said.

The measures appear designed to make it harder for Iran to do business globally. Sanctions targeting Chinese banks, which could cause greater friction in US-China relations, were held back ahead of an important meeting in September.

US President Donald Trump is due to host Chinese President Xi Jinping in the United States in around a month's time. Trump invited Xi during his visit to Beijing in May.