Robbie Williams (John Phillips/Getty) Felix Shepherd (YouTube)

Robbie Williams has sparked outrage among X Factor fans after he asked a transgender contestant what his “birth name” was.

20-year-old trans man Felix Shepherd wowed the judged with his rendition of “All I Want” by Kodaline, and received a standing ovation from the crowd.

However, before Felix – who is from Birmingham and is studying songwriting – began singing, Williams asked him about his history.

Shepherd said he was there to prove to people that he was “more than just a transgender guy.”

Williams responded by asking him: “So when you were born, what was your name?”

When Felix replied with his birth name, Williams asked him: “So when did you know you were Felix?”

Shepherd told the judges about how he realised he was trans when he was in year nine at school, and decided he had to be himself and “tell people.”

Fans of the show took to Twitter to express their support for Shepherd, with many criticising Williams for deadnaming him.

UK LGBT+ charity Stonewall classifies deadnaming as when someone refers to a trans person “using the name they had before they transitioned,” and notes that it can be “deeply hurtful to trans people.”

In one tweet, a fan said asking Shepherd his birth name is “not an acceptable thing to do” and added that it’s “especially not okay when it’s the first question you ask him.”

Another fan, Alex Staddon, said Felix is “lovely” and said they “were really proud to see another trans person on the TV.” However, they wondered why nobody had told Williams that “it’s considered pretty darn rude to ask someone’s birth name? That’s quite an on-the-spot situation to be put in, having to explain oneself.”

Another Twitter user simply said that Williams asking Shepherd his birth name was “a bit disrespectful.”

Somebody else pointed out that you “don’t ask someone what their dead name is”, and said the question was “plain disrespectful and out of boundaries.”

Another fan, Jason Reid, called Williams out for his actions, and said it was “gross and disrespectful” and said that the X Factor is “dead and finished.”

Felix tweeted earlier to say that he was “in no way offended by Robbie’s question” and thanked everybody for their support.

This is not the first time the show has come under fire from LGBT+ fans. In 2016, producers were accused of downplaying the role of contestant Saara Aalto’s same-sex financé.

The show dedicated extensive focus to the personal lives and relationships of some contestants in pre-song VTs, however Aalto’s engagement to Meri Sopanen went nearly entirely unmentioned.