U.S. President Donald Trump made cryptic comments Tuesday about China possibly providing weapons or other potentially lethal war supplies to Iran, a move that would test a U.S. red line on aiding Tehran during the war.

The president suggested in an interview on CNBC Tuesday that the U.S. caught a boat with a ¡°gift¡± from China, after talking about the U.S. restocking its munitions, hinting ¡ª without explicitly saying ¡ª that the present was some form of lethal aid for Tehran.

¡°We caught a ship yesterday that had some things on it, which wasn¡¯t very nice ¡ª a gift from China, perhaps, I don¡¯t know,¡± Trump said. ¡°I thought I had an understanding with President Xi, but that¡¯s alright. That¡¯s the way the war goes right?¡±