R Kelly has been convicted by a federal jury of racketeering in his sex trafficking trial, where prosecutors accused the R&B singer of exploiting his stardom over a quarter-century to lure women and underage girls into his orbit for sex.

Jurors in Brooklyn federal court deliberated for a little more than one day before voting to convict the 54-year-old Kelly on all nine counts he faced.

Known for the 1996 Grammy-winning song 'I Believe I Can Fly', Kelly pleaded not guilty to a racketeering charge and eight counts of violating a federal law making it illegal to transport people across state lines for prostitution.

Prosecutors said Kelly took advantage of his fame and charisma to recruit victims, including some plucked from crowds at his concerts, with the aid of people in his entourage.

Witnesses said some victims had hoped Kelly could jumpstart their careers, only to find he demanded their strict obedience and would punish them if they failed.

Kelly has repeatedly denied sexual abuse accusations.

The singer, whose full name is Robert Sylvester Kelly, is one of the most prominent people tried on sex charges during the #MeToo movement, which amplified accusations that had dogged him since the early 2000s.

R Kelly's lawyers
Lawyers for R Kelly pictured outside the Brooklyn courthouse in New York today

Kelly's alleged victims included the late singer Aaliyah, who Kelly briefly and illegally married in 1994 when she was 15. Aaliyah died in a plane crash in 2001.

Several witnesses testified that Kelly instilled fear if his victims did not fulfill his every need, sexual and otherwise.

Jurors heard how Kelly would compel victims to follow 'Rob's rules', including that they call him 'Daddy' and get permission to eat or go to the bathroom.

One witness hoping to interview him for a radio station said he locked her up for at least two days without food or water before assaulting her.

Witnesses also said Kelly pressed accusers to write 'apology letters' to potentially absolve him of wrongdoing, and concealed before intercourse that he had contracted an STI.

The racketeering charge gave prosecutors leeway to offer evidence that might otherwise be too old to prosecute.

Kelly did not testify in his defence, which lasted about two days.

His lawyers sought, including during cross-examinations of several witnesses, to portray Kelly's accusers as former fans who felt jilted when they fell from his favour, and that their sex with Kelly was consensual.

They also tried to show how some accusers stayed with Kelly long after the alleged abuses began, and questioned why they failed to go to the police or waited years to come forward.

Kelly still faces sex-related charges in Illinois and Minnesota.