“Late Show” host Stephen Colbert on Monday tried to sniff out the truth behind a “weird” moment during President Donald Trump’s meeting last week with oil industry executives at the White House.

Trump complained that the room was too small to hold everyone who wanted to attend, then bragged that the ballroom he’s building would have enough space for larger events.

But he didn’t stop there.

Colbert had a theory about what was really going on.

“OK, he 100% had to fart,” Colbert said, then did an impression of Trump walking away to do just that.

Check it out in his Monday night “Late Show” monologue: