Belgium keeper Thibaut Courtois to miss out on Euro 2024 through injury
"I need to recover fully, so it's better to provide clarity now," the Real Madrid player said.
"If I'm lucky, I might be able to play a match come May, but I'll never be ready for the tournament. I can't be in the goal at 80% or 85%, I should step aside for other good players."
Courtois was sidelined for months in October, after he needed surgery on a torn anterior cruciate ligament in his left knee he suffered during a training session.
He said his decision to sit out Euro 2024 in Germany doesn't have to be a final farewell from the national team, even though he walked out on the squad in June after a spat with coach Domenico Tedesco.
At the time, Tedesco said Courtois had felt overlooked for the team's captaincy, but the goalkeeper said it was a lack of overall appreciation that prompted him to leave.
"That was the wrong decision, for which I apologise to the team and the fans," said Courtois, who has been capped for Belgium 102 times since 2011.
"I still love to play for the national team. But this season I have to focus on Real Madrid, the European Championship does not fit in the picture of a perfect comeback."