President Donald Trump on Monday lashed out at former Russian President Dmitry Medvedev for claiming that multiple countries are “ready to directly supply” Iran with nuclear warheads as a result of the U.S. strikes on key Iranian nuclear sites.

“Did he really say that or, is it just a figment of my imagination?” Trump said of Medvedev, the deputy chairman of Russia’s security council. “If he did say that, and, if confirmed, please let me know, IMMEDIATELY,” he wrote on Truth Social.

Trump chided Medvedev that the “N word” — which he specified stood for “Nuclear” — “should not be treated so casually.” But his response included a similar bout of nuclear saber-rattling, suggesting that the president feels emboldened after ordering the bomb attacks against Iran late Saturday ET.

“By the way, if anyone thinks our ‘hardware’ was great over the weekend, far and away the strongest and best equipment we have, 20 years advanced over the pack, is our Nuclear Submarines,” Trump wrote, calling them “the most powerful and lethal weapons ever built.”

Trump added, “I guess that’s why Putin’s ‘THE BOSS.’”