President Trump threatens China with 50% tariffs over reports suggesting plans to export arms to Iran

US President Donald Trump on Sunday threatened to impose 50% tariffs on China after reports emerged that Beijing was preparing to ship a new air defense system to Iran.

“We’re hearing news reports that China is providing[Iran]with shoulder missiles — so-called shoulder missiles, anti-aircraft missiles. I don’t think they would do that… but if we catch them doing something like that, they would be subject to a 50% tariff. This is shocking. “I’ve heard reports that China is supplying (Iran) shoulder missiles, so-called shoulder missiles, anti-aircraft missiles,” Trump said in response to a question about whether previous tariff threats against countries known to be supplying military equipment to Iran would apply to China.

President Trump’s comments were made in a video call with Fox News and came on the same day that CNN reported, citing insiders, that a U.S. intelligence assessment suggests that China’s delivery of manned man-portable air defense systems (MANPADS), shoulder-operated surface-to-air missile platforms, to Iran is imminent.

But President Trump stopped short of confirming the underlying credibility of the reports in an interview with Fox News, saying such reports “don’t mean much to me because they’re still fake.”

Speculation is growing about China’s role in Iran’s war effort.

In the hours after the temporary ceasefire between the United States and Iran last week, the New York Times reported, citing three Iranian insiders, that China was “putting pressure” on Iran to agree to a ceasefire.

In response, Chinese Foreign Ministry spokesperson Mao Ning said at a press conference on April 8 that China had “made active efforts to promote peace negotiations and end hostilities,” but did not acknowledge any role in official mediation.

Dylan Lo, an associate professor of public policy and world affairs at Singapore’s Nanyang Technological University, said China, one of Iran’s closest allies, had until recently been “quite reluctant” to support Tehran.

“China appears to be exercising its influence selectively and, as seen in recent developments, is prepared to engage in a more proactive manner when it senses an opportunity to exert influence,” Lo added.

China is one of Iran’s most vocal sources of support, but there have been no official reports that Beijing has provided military or financial support to Tehran since hostilities began on February 28.

If confirmed, Low said, China’s arms deliveries to Iran would be a “starting point” for Beijing’s response to the situation in the Middle East, adding that even though the weapons themselves may not play a decisive role in Iran’s retaliatory activities, it “brings greater uncertainty” to the overall situation.

Analysts have previously suggested to CNBC that China’s support for Iran is likely motivated by Beijing’s own material and economic interests rather than a meaningful shift in foreign policy.

Zhongyuan Zoe Liu, a senior fellow for China studies at the Council on Foreign Relations, told CNBC last Friday that China’s economy remains fundamentally dependent on maritime exports and would therefore be vulnerable to an economic downturn due to the prolonged closure of the Strait of Hormuz.

In 2025, the Chinese government will reportedly buy more than 80% of Iran’s heavily sanctioned oil exports, meeting more than 10% of China’s total demand, according to estimates by maritime information firm Kpler.

As one of Iran’s key economic partners, a Chinese-flagged oil tanker that sails through the Persian Gulf is reportedly one of the few vessels allowed to pass through the Strait of Hormuz since the start of hostilities.

But gasoline prices in China are still up about 11% since Tehran closed the Strait of Hormuz, according to figures from China’s National Development and Reform Commission, putting a cap on further fuel price increases as authorities seek to protect consumers from further fallout from the war.

Just as reports of Chinese arms shipments to Iran remain unverified, President Trump’s intentions in carrying out his threat of tariffs on China are similarly unclear.

Since the beginning of the U.S.-Israel war in Iran, President Trump has oscillated between threatening to annihilate the Iranian people and offering to withdraw from diplomacy, with critics often labeling his tendencies as “TACO” (Trump Always Chickens Out).

In an inflammatory Easter Sunday post on his Truth social account, President Trump threatened to bomb critical Iranian infrastructure, including bridges and power plants, if the Iranian government did not reopen the Strait of Hormuz.

This was followed by another post on Truth Social in which President Trump said that if the Strait of Hormuz was not opened by the April 8 deadline, “the entire civilization will perish tonight,” a threat that did not materialize.

Still, Lowe emphasized that President Trump has also shown he is following through on his warnings.

“Venezuela, Iran, global tariffs are instructive examples. If[Trump]had solid evidence that China was prepared to substantially support Iran, he would respond,” Low said.

President Trump on Sunday announced a complete blockade of ships leaving the Strait of Hormuz after peace talks between Iran and the United States collapsed, with Iranian state media citing “unreasonable demands” by a US delegation led by Vice President Vance.

President Trump is scheduled to hold a summit meeting with Chinese President Xi Jinping in Beijing on May 14th and 15th.

The Chinese embassy in Singapore did not respond to CNBC’s request for comment.

—CNBC’s Evelyn Cheng contributed to this report.