Paul McCartney has confessed to Channel 4 what after Thom Yorke, vocalist of Radiohead, worked in 2000 with PJ Harvey (where he did a duet with the singer, in addition to helping as a backup singer on two other songs), he decided to offer her a collaboration to create music together. Yorke rejected the idea, saying "I'm not comfortable working with music other than my band's and mine."
But if you are not comfortable making music other than Radiohead And his, why do I collaborate with PJ Harvey?