President Donald Trump threatened China with a "staggering" 50% tariff if it provides military assistance to Iran.

During a Sunday interview, Trump said that any country, including China, that supplies weapons to Tehran would face steep economic consequences, escalating tensions between the world's two largest economies.

"If we catch them doing that, they get a 50% tariff," Trump told Maria Bartiromo on Fox News' "Sunday Morning Futures," specifically referencing reports that China may be providing shoulder-fired anti-aircraft missiles to Iran.

He noted that the tarfiff would be "a staggering amount."

The warning comes amid mounting intelligence concerns.

U.S. intelligence agencies believe China may have shipped portable air defense systems, known as MANPADS, to Iran, The New York Times reported.

The weapons can target low-flying aircraft and pose a renewed threat to U.S. forces if hostilities resume.

CNN reported that U.S. intelligence indicates China is preparing to deliver new air defense systems to Iran within the next few weeks.

Chinese officials have denied the allegations, insisting Beijing has not provided weapons to any party in the conflict and is working to de-escalate tensions.

Still, U.S. officials remain wary, noting that even indirect support through third-party channels would represent a significant escalation.

Trump expressed skepticism that China would risk damaging its relationship with the U.S., but did not rule out limited early involvement.

"I have a very good relationship with President Xi," Trump said. "I don't think they would do that anymore — but maybe they did a little bit at the beginning."

The remarks highlight growing concerns in Washington that adversaries such as China and Russia could exploit the Iran conflict to challenge U.S. power.

Intelligence assessments cited by the Times and CNN indicate China has continued supplying Iran with dual-use technology and components that can support military production, even as it publicly positions itself as neutral.

At the same time, Trump reiterated his administration's core objective in the region: preventing Iran from acquiring nuclear weapons.

He described recent negotiations with Tehran as productive but ultimately unsuccessful because of Iran's refusal to abandon its nuclear ambitions.

"They want to have nuclear weapons. They're not going to have nuclear weapons," Trump said.

Trump also pointed to what he described as the overwhelming success of recent U.S. military operations, claiming Iran's military infrastructure has been largely "obliterated."

He argued that Tehran now lacks leverage and will eventually return to the negotiating table on U.S. terms.

Despite the tough rhetoric, the potential for Chinese involvement adds a new layer of complexity to the conflict.

Analysts note that Beijing relies heavily on Iranian oil and may seek to balance its economic interests with its desire to avoid direct confrontation with the U.S.

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