In a message sent through his Secretary of State to the archbishop of Los Angeles, José Gómez, Pope Francis assures his "spiritual closeness" to all those affected by the fires.
"Entrusting the souls of the deceased to the loving mercy of Almighty God, His Holiness sends heartfelt condolences to those who mourn their loss. He likewise prays for the relief efforts of the emergency service personnel and imparts his blessing to all as a pledge of consolation and strength in the Lord."
Some 180,000 people have been evacuated. The death toll is currently limited to 11 though it is thought it could rise as more victims are discovered.
The disaster caused the cancellation of US President Joe Biden's visit to Rome, where he was due to meet Pope Francis on January 10. President Biden, 82, will hand over power to Donald Trump on January 20.