Actor Daniel Radcliffe shared a lengthy and heartfelt message Monday in response to recent tweets from “Harry Potter” author J.K. Rowling that have been widely condemned as transphobic.

In a blog post for the Trevor Project, an organization that provides crisis intervention and suicide prevention services for LGBTQ youth, Radcliffe, who played the titular boy wizard in all eight “Harry Potter” films, made clear where he stands on Rowling’s weekend Twitter outburst.

“While Jo [Rowling] is unquestionably responsible for the course my life has taken, as someone who has been honored to work with and continues to contribute to The Trevor Project for the last decade, and just as a human being, I feel compelled to say something at this moment,” Radcliffe wrote.

“Transgender women are women. Any statement to the contrary erases the identity and dignity of transgender people and goes against all advice given by professional health care associations who have far more expertise on this subject matter than either Jo or I.”

Rowling drew sharp criticism on Saturday when she remarked on a Devex op-ed about healthcare inequality that used the phrase “people who menstruate” to be more inclusive. “‘People who menstruate.’ I’m sure there used to be a word for those people,” she tweeted. “Someone help me out. Wumben? Wimpund? Woomud?”

The insensitive comment sparked an immediate backlash from social media and transgender activists — but Rowling doubled down, arguing, “If sex isn’t real, there’s no same-sex attraction. If sex isn’t real, the lived reality of women globally is erased. I know and love trans people, but erasing the concept of sex removes the ability of many to meaningfully discuss their lives. It isn’t hate to speak the truth.”

Among the many who called Rowling out were LGBTQ rights organization GLAAD, which stated that “there is no excuse for targeting trans people”; “Mrs. America” star Sarah Paulson, who advised Rowling to “shut up”; and Scottish actress Katie Leung, who played Hogwarts student Cho Chang in the “Harry Potter” franchise and shared various ways to support the transgender community.

“78% of transgender and nonbinary youth reported being the subject of discrimination due to their gender identity,” Radcliffe continued in his post. “It’s clear that we need to do more to support transgender and nonbinary people, not invalidate their identities, and not cause further harm. …

“To all the people who now feel that their experience of the books has been tarnished or diminished, I am deeply sorry for the pain these comments have caused you,” he added. “I really hope that you don’t entirely lose what was valuable in these stories to you.”

Radcliffe ended his note with some words of comfort for Harry Potter fans disappointed by Rowling’s behavior:

“If these books taught you that love is the strongest force in the universe, capable of overcoming anything; if they taught you that strength is found in diversity, and that dogmatic ideas of pureness lead to the oppression of vulnerable groups; if you believe that a particular character is trans, nonbinary, or gender fluid, or that they are gay or bisexual; if you found anything in these stories that resonated with you and helped you at any time in your life — then that is between you and the book that you read, and it is sacred.

“And in my opinion nobody can touch that. It means to you what it means to you and I hope that these comments will not taint that too much.”