Trump and his Japanese host Shinzo Abe began by delicately spooning out the food into the pond to the waiting koi, which had been rounded up by a clapping Japanese aide.
The US leader apparently lost patience with this method and upended his entire wooden box into the pond.
The incident caused outrage among fish lovers on Twitter, with many pointing out that fish cannot absorb a large amount of food at a time.
US Secretary of State Rex Tillerson, standing just behind Trump, appeared to break out in laughter at his boss's no-nonsense approach to koi feeding.
Our only hope is that Donald Trump exercises greater control over our nuclear arsenal than he does a box of fish food.— John Iadarola (@johniadarola) November 6, 2017
Trump was supposed to feed the koi by the spoonful with PM Abe but quickly got impatient and dumped the whole box of food into the pond. pic.twitter.com/MZxNfqTRDB— Yashar Ali (@yashar) November 6, 2017
You proved my point. Trump has NO clue about what is tradition and custom in other nations. Dumping fish food is just the latest.— ((Wendy McClelland)) (@wendyweb47) November 6, 2017
I don't think Trump has ever fed a fish in his life— Johanna (@serialbear) November 6, 2017
Though many of his supporters rushed to his defence saying the president's way of feeding fish wasn't wrong
Day 300 of the Presidency...Liberals have such terrible leadership, they resort to poking fun at Trump's way of feeding fish for political points
A sad display, indeed— Mark Rubello (@MarkRubello) November 6, 2017
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Trump getting hammered for feeding fish when Obama was caught doing similiar thing! https://t.co/VxC2FcGLdy— Karl Walnut (@CryinHillary) November 6, 2017