Saliba has been experiencing back pain in recent weeks following a long season with Arsenal, who won the Premier League title and reached the Champions League final. France coach Didier Deschamps had said recently the player would be fit for the World Cup.
"William Saliba will not take part in the day's team training. Theo Hernandez is also rested as a precaution as is Aurelien Tchouameni," the FFF said in a statement.
France, who won the title in 2018 and reached the final four years later, kick off their Group I matches against Senegal on Tuesday before facing Iraq and Norway.
The 2026 World Cup will be held from June 11th to July 19th in the United States, Canada and Mexico. The tournament will feature 48 national teams and will be played in 16 modern stadiums.
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