Darren Criss is apologizing for making an off-color joke about Caitlyn Jenner.

The former "Glee" star reportedly made a reference to Jenner during a Broadway performance of "Hedwig and the Angry Inch" earlier this week.

A member of the audience who was present at the performance tweeted that Criss, in character as Hedwig, improvised the line “man, woman, moman, wan, Bruce Jenner, whatever you are” and called it “very distasteful.”

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In response to some backlash, Criss issued an apology on Facebook.

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“I want to sincerely apologize to Caitlyn Jenner, all transgender people, and anyone who was offended for my words on stage during Tuesday evening’s performance,” he wrote in a Facebook post on Thursday evening.

“In no way do the remarks reflect my personal belief system or my support for transgender people,” he wrote. “However, I do realize the severity of the comment and the weight that words can carry and for that, I take full responsibility.”

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The 28-year-old actor-singer also commended Jenner “on her strength and for spreading acceptance around the globe.”

Criss, a vocal supporter for LGBT rights, ended his apology promising to continue his work with the community.

“I have been and remain a proud and unwavering ally of the LGBTQIA community, and will continue to walk alongside my friends on the road to full equality and acceptance," he concluded.

On Friday, following the Supreme Court’s decision ruling same-sex marriage to be legal in all 50 states, Criss took to social media to celebrate the landmark moment.

“It’s truly a beautiful day! Hell yeah. Lots of reasons to go outside and celebrate for. #LoveWins,” he wrote.

Criss is currently on Broadway playing the title character in "Hedwig and the Angry Inch" through July 19, when Taye Diggs will take over the role.