Zelensky says Trump "lives in a bubble of disinformation" with discord sown by Russia.
The Ukrainian president responded to Trump's comments the night before.
He says he "never comments on popularity ratings, especially my own or those of other leaders," but notes that the latest poll shows that 58% of Ukrainians trust him.
"So if someone wants to replace me now, that won't work," he says.
He also highlights "a lot of disinformation coming from Russia," saying that this data appears to be being shared with the US as well.
"Unfortunately, President Trump, with all due respect to him as the leader of a nation that we respect greatly... lives in this bubble of disinformation," he says.
Zelensky says he will consider collecting more data on trust in key global leaders to counter Russian disinformation, warning of the "circle of disinformation around President Trump," which he says includes representatives linked to the Hungarian and Slovak governments.
"This is worrying. Everything they are doing is aimed at ensuring that Ukraine is weak," he says.