Eagles Of Death Metal frontman Jesse Hughes took to the stage at a concert celebrating the life of Nick Alexander - the Briton killed in the Paris attacks in November last year.
Mr Alexander was working as a roadie for the US band when three terrorists stormed the Bataclan theatre on November 13.
He was among 89 people killed in the attack.
Hughes appeared moved as he paid tribute to his friend on stage at the Shepherd's Bush Empire in London - just days after the first anniversary of the massacre.
Dressed in white, he told the crowd as he closed his set: "I'm going to do an acapella song, specifically for my dear friend Nick, who I miss every day.
"And I think what's happening here is one of the most beautiful things you could have asked for.
"The only answer that there is for things that are terrible is love and beauty and peace, and right now you are proving that beyond a shadow of doubt."
Hughes's performance came after it was claimed he was turned away from Sting's concert at the Bataclan on Saturday by the venue's management.
The American singer provoked anger in the months following the massacre when he suggested Bataclan security staff were at fault in the attack, but later apologised.
Hughes was joined on the line-up for the gig - dubbed A Peaceful Noise - by rockstars including Maximo Park, Travis frontman Fran Healy, Supergrass's Gaz Coombes and Chas And Dave.