Courtois, widely regarded as one of the best keepers in the world, was left out of the Belgium squad for the European Championship following a row with Tedesco last year. He was replaced by Koen Casteels for the Euros.
"I feel privileged to have had the honour of wearing the national jersey. Not even in my wildest dreams could I have imagined being able to do so more than 100 times," Courtois posted on his social media accounts.
"Unfortunately, following the events with the coach and after much reflection, I have decided not to return to the Belgian national team under his management.
"In this matter, I accept my share of responsibility. However, looking forward, my lack of confidence in him would not contribute to maintaining the necessary atmosphere of cordiality."
The goalkeeper, who suffered an injury but recovered in time to help Real Madrid win the Champions League in June, added the Belgian FA has accepted his position and the reasons that led to the decision.
"I regret possibly disappointing some fans but I am convinced that this is the best course of action for Belgium, as it closes a debate and allows the team to focus on pursuing its goals. Thank you for your unwavering support, love, and understanding," Courtois said.
Tedesco's tactics raised questions about whether he was the right man for the job after Belgium were eliminated by France in the last 16 of the Euros.
The Italian-born German manager began his tenure in February 2023 and signed a contract extension before the start of the Euros.
However, the team that spent nearly three years at the top of the world rankings and reached the semi-finals of the 2018 World Cup has endured mediocre results under Tedesco.