President Donald Trump issued a warning to China on Friday, saying Beijing would face serious consequences if it follows through on reports that it plans to supply Iran with air defense weapons during the ongoing conflict.

Speaking to reporters outside the White House, Trump made clear that such a move would not be tolerated.

“If China does that, China is gonna have big problems, OK?”

U.S. intelligence officials have indicated that China may be preparing to covertly transfer shoulder-fired anti-aircraft weapons, known as MANPADs, to Iran through intermediaries in the coming weeks, according to CNN. The alleged plan is said to be designed to conceal the origin of the weapons.

These systems, which use heat-seeking technology to target aircraft engines, have already posed a significant challenge during the war. One such missile nearly struck an F/A-18 Super Hornet in a recent incident.

Trump also referenced a separate case involving a downed American aircraft earlier in the conflict.

The American F-15 fighter jet shot down by Iran on April 3 was hit by a “handheld shoulder missile, [a] heat-seeking missile,” according to Trump.

China has strongly denied the allegations, with its embassy rejecting claims that it intends to provide Iran with military equipment.

“As a responsible major country, China always abides by international law and its international obligations, and never provides weapons to any party to the conflict,” the Chinese embassy said in a statement.

“China firmly rejects the circulation of speculative, misleading, and false information targeting China.”

At the same time, Beijing has faced accusations of assisting Iran with intelligence during the conflict. Iranian Foreign Minister Abbas Araghchi suggested that ties between the countries remain close and extend into military cooperation.

“Russia and China are our strategy partners, and we have had close cooperation in the past, which is still continues [sic], and that includes military cooperation as well,” Araghchi told MS Now.