The US president baffled viewers when he stopped an announcement on live TV to take two sips of water - a move similar to one that Trump mocked Senator Marco Rubio for during the 2016 campaign.
Mr Trump was making a speech following his 11 day-trip around Asia when he suddenly decided he needed to quench his thirst.
The president paused and began to look for water and after coming up empty, he said: "They don't have water. That's OK."
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Reporters pointed out a bottle of Fiji water under the podium, which Mr Trump picked up and dramatically stared down the lens of the camera while opening the bottle. He then took a gulp.
The moment has been compared to Senator Marco Rubio's awkward water bottle sip, which ironically Mr Trump mocked.
During his campaign trail in 2016, Mr Trump made fun of Senator Rubio as he mockingly paraded a water bottle on stage and tossed it around.
Mr Rubio jokingly tweeted that Mr Trump had to work on his water drinking technique after the live announcement on Thursday.
"Similar, but needs work on his form. Has to be done in one single motion & eyes should never leave the camera. But not bad for his 1st time," he tweeted.
Mr Trump gave updates from his South Korea, China, Vietnam, Japan and Philippines trip and reiterated that America's standing in the world has never been better.