The 21-year-old star split from on-and-off girlfriend Selena Gomez last year and has since been linked to close friends including Kendall Jenner, Hailey Baldwin and Playboy model Xenia Deli, reported E! Online.
Speaking on 'The Ellen Degeneres Show', he said, "I'm single ladies, and ready to mingle... But I'm in a place now ... I don't know if I'm ready for a relationship right now."
Bieber also agreed with chat show host Ellen when she suggested Madonna had been flirting with him when they appeared on the show together earlier this year.