Former Glee star, Darren Criss, has apologised for making an insensitive remark about Caitlyn Jenner’s transition while on stage in Broadway’s ‘Hedwig and the Angry Inch’.

During a performance of the smash hit musical about a German transgender punk rocker last week, Criss (28) upset some audience members with ad-libbed lines about Caitlyn Jenner’s transition. He said while in character on stage, “Man, woman, moman, wan, Bruce Jenner, whatever you are.”

Audience members questioned the actor’s intention behind the comments over Twitter following the show, which prompted Criss to respond on Facebook. He apologised for the remarks and commended Jenner for her “strength” and for “spreading acceptance around the globe.”

The actor – who became well known for his portrayal of Blaine Anderson, a gay show choir singer on Glee – is a long time advocate for LGBT rights. He is an active supporter of LGBT youth charity, The Trevor Project.