England captain Owen Farrell has made himself unavailable for the 2024 Six Nations "in order to prioritise his and his family's mental wellbeing".
England start their Six Nations campaign on 3 February in Italy and end it with a game in France on 16 March.
Saracens said Farrell, 32, will continue to play for and captain them during his international absence.
"Everyone at England Rugby is fully behind Owen's decision," said England head coach Steve Borthwick.
"Since making his debut, he has been an integral part of the England set-up for over a decade and the demands on elite athletes are extremely challenging.
"He is an exemplary player, captain and leader and always gives his all for his country.
"It is with typical courage that Owen has made this decision to open up in this manner. Together with all of us at England Rugby, I will do everything I can to ensure that he has the support he requires going forward."
More to follow.