Lady Gaga apologized early Thursday for a previous collaboration with singer R. Kelly, just days after the Lifetime docuseries "Surviving R. Kelly" shed new light on sexual abuse allegations against the R&B star.

>> Read more trending news

"I stand behind these women 1000%, believe them, know they are suffering and in pain, and feel strongly that their voices should be heard and taken seriously," Gaga tweeted of the women's claims, which Kelly has denied. "What I am hearing about the allegations against R. Kelly is absolutely horrifying and indefensible."

Related: Report: R. Kelly under investigation for abuse documented by ‘Surviving R. Kelly’

The "A Star Is Born" actress promised to pull her 2013 song "Do What U Want (With My Body)," a duet with Kelly, from streaming services and Apple's iTunes store. She added that she "will not be working with him again."

"As a victim of sexual assault myself, I made both the song and video at a dark time in my life," she wrote. "My intention was to create something extremely defiant and provocative because I was angry and still hadn't processed the trauma that had occurred in my own life."

Related: 'Let these girls go': Alleged victim's family begs R. Kelly to stop reported abuse against women

Gaga, 32, said she used "poor judgment" when she recorded the song and apologized for not speaking out against Kelly sooner.

"I can't go back, but I can go forward and continue to support women, men and people of all sexual identities, and of all races, who are victims of sexual assault," she said.

>> Read the full statement here

What You Need to Know: "Surviving R. Kelly" Allegations