The man was sitting about 10 rows back on the U.S. side of the room among the press, in the second seat from the aisle. He held up a sign that read "Nuclear Weapons Ban Treaty."
Security questioned him for a couple minutes before the ejection. As he struggled against guards — at one point waving the sign around and trying to keep it out of one man's hands — others in the room pulled out phones and started recording the incident.
The ejection happened as Trump and Putin held a closed-door meeting with aides at the Presidential Palace.