Macy Gray has come under fire for making controversial comments about transgender women.

The I Try singer appeared on Piers Morgan's Uncensored TV show on Monday and controversially said she doesn't consider those who transition from male to female women, even if they've undergone surgery.

"(A woman is) a human being with boobs. How about you start there? And a vagina!" she said. "I will say this and everybody's gonna hate me but - as a woman - just because you go change your parts, it doesn't make you a woman, sorry... I know that for a fact.

"You want me to call you a 'her', I will, because that's what you want but that doesn't make you a woman just because I call you a 'her' and just because you got a surgery."

The 54-year-old insisted she supports trans rights to fairness and equality, except in competitive sporting situations, but stated that being a woman is about more than body parts.

"Women go through a completely unique experience and surgery and finding yourself doesn't change that. Being a little girl is a whole epic book, you know? You can't have that just because you want to be a woman," Gray added.

Morgan then mentioned the controversy surrounding Harry Potter author J.K. Rowling over her transgender comments, and she replied, "I don't think you should be called transphobic just because you don't agree with, you know. There is a lot of judgement and throwing stones at people for just saying what it is."

Gray received criticism on social media, with many users calling her "transphobic" and a TERF (trans-exclusionary radical feminist). Defending herself on Twitter, she wrote, "There is no bigger admirer of lgbt community than your truly. it takes real balls to be honest about who you are. 'woman' is a title that you earn and become. just like 'man.' there are plenty of females who aren't women yet and every girl gets that."

The singer found herself a supporter in Rowling, who tweeted, "Today feels like a good day to ensure I've bought @MacyGraysLife's entire back catalogue (fire emoji)."