The singer was due to be presenting alongside Kelly Osbourne at the bash, which is taking place at the London Arena on Sunday.
The N'Sync star broke his foot while rehearsing for the awards, and doctors have told him to rest for two weeks.
"I am sorely disappointed that I must miss any scheduled events. However, I must adhere to my physician's recommendations and rest.
"I look forward to being able to perform again and hope to see all my fans soon," he said.
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