".
Trump was quizzed by his son Don Jr in a video on YouTube put together for Father's Day.
During the 20-minute chat, Don Jr asks if the President will ever consider "letting us know there is aliens" before he leaves office.
He said: "This is the only thing I really want to know. Would you ever open up Roswell and let us know what's really going on."
Roswell is regarded as one of the most notorious UFO incidents.
'VERY INTERESTING'
It happened when a rancher discovered a mysterious crash site on his pasture in New Mexico in 1947.
Responding to his son, the President said: "So many people ask me that question, it sounds like a cute question.
"There are millions and millions of people who want to go there, who want to see it.
"I won't talk to you about what I know about it, but it's very interesting."
The President has previously said he "doesn't particularly believe" in aliens but has admitted holding meetings on sightings of UFOs.
Speaking last year, he said: "They do say, and I've seen, and I've read, and I've heard, and I did have one very brief meeting on it.
"But people are saying they're seeing UFOs. Do I believe it? Not particularly."
He also commented on the release of UFO footage by the Pentagon earlier in April - describing it as a "hell of a video".
“I just wonder if it’s real," Trump said.
The Department of Defense opted to declassify the three clips of US Navy pilots interacting with UFOs.
The clips show three separate incidents involving "unidentified aerial phenomena," one from November 2004 and two from January 2015.
Trump has previously declassified thousands of files, including on the JFK assassination.
Videos of the Tic Tac have gripped the nation, with one of the pilots, Commander David Fravor, saying it was performing maneuvers impossible for a manmade craft.
Fravor claims the UFO also jammed the US Navy's radar, describing this as "technically an act of war", as it flew near aircraft carrier USS Nimitz.
The Pentagon quietly set up a top secret program to research UFOs more than 10 years ago called The Advanced Aviation Threat Identification Program (AATIP).
And then Trump unveiled the new US Space Force in 2018, with some experts suggesting he may have done so after learning about American UFO secrets.
Nick Pope, who used to run the British defense ministry's UFO project, said it would be “nonsense” to suggest the President is being kept in the dark about potential UFO threats.
Pope told Sun Online: “There are conspiracy theories suggesting President Trump's plans for a Space Force reflect a need to protect Earth against hostile aliens.
"There were similar conspiracy theories about President Reagan's Star Wars plan."
He added: “While there may not be an alien connection, President Trump surely knows all of America's UFO secrets - some of which were released earlier this year as part of the AATIP project - and this may have contributed to his keenness to develop a military Space Force."
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