The Who Wants to Be a Millionaire host was speaking at ITV's schedule launch when he made the comments.
At the event, Clarkson was being interviewed by Joel Dommett who asked him who were some of the big names set to appear on the next series of Who Wants to Be a Millionaire.
In response, Clarkson said: "Eddie Izzard obviously is very bright so he was fun. She, them, it. I don't know what you say! She? She?"
The audience then shouted out "they" at the former Top Gear presenter even though Izzard has never gone by they/them pronouns.
Clarkson then said: "They... whatever he is. I knew there was a word. There was a pronoun I had forgotten. They were very good."
Izzard has gone by she/her pronouns since 2020 after requesting to be referred to as such on Sky's Portrait Artist of the Year.
Clarkson was criticised on social media for his remarks with one person writing: "No fan of Eddie Izzard but the comments made by Jeremy Clarkson referring to her as ‘he,she or it’ are disgraceful."
Elsewhere at the event, Clarkson admitted to preferring to hosting the normal version of Millionaire as opposed to the celebrity one.
He said: "Honestly I much prefer doing the ordinary one. With the celebrity one, I don't have a f***ing clue who half the people are. I have to read up on who they are."
Who Wants to Be a Millionaire originally started airing in 1998 and was hosted by Chis Tarrant.
This version of the show ran until 2014, airing a total of 582 episodes.
Who Wants to Be a Millionaire was later revived by ITV in 2018 with Clarkson as the new host.
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