Who said "A trainer and their Pokémon need to work as one."?

This quote is attributed to Ash Ketchum.

A trainer and their Pokémon need to work as one. - Ash Ketchum

"A trainer and their Pokémon need to work as one."

Ash Ketchum

"Gotta catch 'em all!"

"I'm gonna be a Pokémon Master!"

"There's no such thing as a useless Pokémon. It's the trainer that makes the difference."

"The important thing is not how strong a Pokémon is, but the bond between a trainer and their Pokémon."