United States President Donald Trump said on Friday that he does not believe China or Russia are “participating” in the ongoing Iran conflict but warned that any involvement would be “very bad for them”.

“President Xi, at our recent meeting in Beijing, China, told me that he would not, under any circumstances, give or sell weapons to the Islamic Republic of Iran — and that statement included Chinese companies,” he wrote on Truth Social.

Trump said Russian President Vladimir Putin had also told him that Moscow would not sell weapons to Iran, adding that he believed Russia and China were not involved in the conflict.

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“If they did, it would be very bad for them — certainly not in their best interests,” Trump posted.

The United States and Iran have been at war since the US and Israel launched strikes in February that killed senior Iranian officials, including the country’s supreme leader.

Four people familiar with US intelligence said Iranian strikes on CIA targets in the Gulf earlier in the war had prompted US intelligence agencies to investigate whether Russia was providing Iran with targeting information or drone technology. The Kremlin declined to comment on the report on Thursday.

The United States has sanctioned individuals and companies in Russia and China for helping Iran acquire weapons.