Pokemon protagonist Ash Ketchum and his loyal sidekick Pikachu are leaving the show after 25 years.

It comes after the character fulfilled his dream to “be the very best, like no one ever was” and became the top trainer in the world.

It came after years of defeats and upset for the perpetual 10-year-old during the anime franchise, which features over 900 animal-like characters called Pokemon which can be caught, trained and used to battle one another.

Now, the next series of the anime show will focus on dual protagonists named Liko and Roy, joined by three Paldea starter Pokemon.

Sarah Natochenny, said it was “an extraordinary privilege” to have voiced the English version of Ketchum and other characters since 2006.

“No matter what lies beyond his final chapter, he’ll live forever in the hearts of many generations to come,” she tweeted.

“I’ll keep him present for all of us in every way I can.”

A collection of special episodes will be released commemorating Ash and Pikachu’s adventures together.

The show’s producers said they would “offer a glimpse at what the future may hold” for Ash, but would be the “final chapter” for the pair.

The producers said the next series would “represent everything [the fans] love about Pokemon animation, including action, adventure, friendship and Pokemon”.

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The Pokemon franchise first became popular in the UK when the trading cards were released allowing children and adults alike to trade and battle Pokemon.

The long-running TV show followed alongside dozens of video games, including mobile game Pokemon GO, which used augmented reality to allow users to “catch” Pokemon in their homes and on the streets.