This movie included a little boy and some animals. At one point the boy finds himself caught in between 2 kings which can't agree with each other and say they have nothing in common, the little boy comes to the conclusion that both of them agree to disagree and that's the only thing they agree on. And then at some point he meets some dude that makes boy and his 3 friends do some useless tasks like one is moving water out of a bucket into a well, and another one is moving sand bit by bit with some tweezers. It was an older movie either from the 80's or 90's?

Sounds like

The Phantom Tollbooth

Appreciate it I'll let you know if it was the right one or not.

Was this a cartoon made by Chuck Jones?

Yes
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