The U.S. government says it's doing everything it can to get Brittney Griner home ... but now there's a Justin from Canada looking to help out, too -- and it ain't Trudeau.
Justin Bieber is reacting to Griner's 9-year sentence for bringing cannabis oil into Russia ... saying it "hurts" to hear the news, but he doesn't want to sit around and do nothing.
"If anyone knows of anyway (sic) I can help please let me know."
Bieber is just one of many notable figures furious over the sentencing -- Kyrie Irving called on President Joe Biden and Vice President Kamala Harris to provide more info about Griner's status.