The United Nations gender equality entity, alongside a host of musicians, has thrown its support behind US singer Kesha, after a judge ruled she could not break a contract with a producer whom she accused of rape.

Kesha fans protest outside New York State Supreme Court. (Photo by Roy Rochlin/Getty Images)

Kesha broke down in court on Friday after a Manhattan Supreme Court judge ruled she was legally obliged to produce five more albums with Sony Records, maintaining her association with producer Lukasz Gottwald, who she says drugged and raped her when she was 18 years old.

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Twitter lit up with the #FreeKesha hashtag soon after the decision, with Lady Gaga, Lorde, and Kelly Clarkson among the musicians, actors and well-wishers throwing their support behind the singer.

Among those sharing their support for Kesha was UN Women, which shared an article discussing how the “Free Kesha” campaign could “shine a light on how hard it is to seek justice in cases of alleged rape”.

The 28-year-old sued her long-time producer in 2014 .

“I cannot work with this monster,” Kesha said in a sworn statement in August.

Court documents show the accusations also included years of emotional torment in which it is alleged the 42-year-old berated her about her weight, resulting in rehabilitation for an eating disorder.

Kesha alleges the producer threatened to destroy her career if she went public.

Lady Gaga has thrown her weight behind Kesha. Image: Getty

Gottwald, known as Dr Luke, said through an attorney that the accusations were “malicious lies” being spread in an attempt to cut short her contract.

“All of their horrific allegations of abuse, threats and other purported misconduct by me against Kesha are completely untrue and deeply hurtful,” he said in a sworn statement in December.

He has not been charged with any crime and his lawyers say he “wants his name restored.”