Trump's hits against Rubio's water-drinking technique stemmed from a 2013 speech, years before Trump had even expressed serious presidential aspirations.
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.
President Donald Trump went on television on Wednesday to recap his just-completed trip overseas, but it was his pause to refresh that ended up making news. It was a move he once mocked Marco Rubio for, and the Florida senator wasted little time in teasing Trump on Twitter. When he realised that there was no water bottle, he came up to announce: "They don't have water". The senator joked after the president's speech that Trump needs to work on his form.
The presidential sip recalled the now infamous 2013 moment when Rubio slugged from a water bottle while delivering the GOP rebuttal to former President Barack Obama's State of the Union address. After opening it with some apparent difficulty, he took a quick, awkward drink and continue on with his speech.
Marco Rubio Responds To Donald Trump's Press Conference Water Sip
Trump pulled a bottle of water out of his pocket and exclaimed, "It's Marco!"
The throwaway moment did not go unnoticed by the president's critics on Twitter.
Dry mouth got in the way.
Trump tweeted five separate times about Rubio drinking water, and later made fun of him doing so on the campaign trail. "But not bad for his 1st time", Rubio wrote. The White House did not immediately respond to a request for comment on the social media reaction.
Oil steady as expected output curbs balance U.S. supply
EIA data confirming a surge in crude oil stockpiles could send markets deeper into negative territory. USA crude imports rose last week by 261,000 barrels per day.