Etta James has threatened to "arse whip" Beyonce Knowles.
The legendary singer has slammed Beyonce's rendition of 'At Last' - a song which Etta, 71, is famous for performing - at US President Barack Obama's inauguration, claiming she "can't stand" the singer.
Speaking at a Seattle concert earlier this week, Etta said: "You guys know your President, right? You know the one with the big ears? Wait a minute, he ain't my President, he might be yours, he ain't my President. You know that woman he had singing for him, singing my song - she's going to get her a*s whipped.
"The great Beyonce. I can't stand Beyonce! She has no business up there, singing up there on a big ol' President day, singing my song that I've been singing forever."
Etta was not the first person to sing the song, but her version is the best known.
Beyonce - who portrayed Etta in her latest movie 'Cadillac Records' - was asked to perform 'At Last' at the ceremony.