President Donald Trump made a bizarre claim Thursday on Air Force One after being asked about a recent video clip that went viral online. The clip, in which Barack Obama said that aliens are real but that he hadn’t seen them,

The President cited “tremendous interest” in the topic after his predecessor Barack Obama suggested the existence of extraterrestrial life.

Obama replied “They’re real, but I haven’t seen them, and they’re not being kept in … what is it …?” “Area 51?” the interviewer responded. Then Obama said, “Area 51. There’s no underground facility. Unless there’s this enormous conspiracy, and they hid it from the president of the United States.”

Liberal influencer Brian Tyler Cohen interviewed Obama for a video that was published Feb. 14, touching on a variety of topics, from racism to ICE raids. But it was a lightning round at the end that got the most attention, with Cohen asking, “Are aliens real?”

Area 51 is a U.S. Air Force Base in Nevada, and has long been the subject of conspiracy theories stemming from the belief that the U.S. government keeps evidence of alien contact on site, including spacecraft and specimens.

The president’s announcement came after he criticized former President Barack Obama for suggesting aliens are real.