NEW YORK (REUTERS) - R. Kelly said on Wednesday (Sept 22) he will not testify in his own defence at his sex trafficking trial in Brooklyn, where the government accused the R&B singer of grooming and sexually abusing women and underage girls.

Kelly, 54, announced his intention after five witnesses spoke in his defence over nearly two days, following four and a half weeks of testimony from prosecution witnesses.

"No, ma'am," Kelly told US District Judge Ann Donnelly when asked if he would testify, which he is not required to do.

Kelly also said he understood the implications of his decision.

Closing arguments are expected to begin later on Wednesday, and jurors could begin deliberating on Thursday.

Kelly, whose full name is Robert Sylvester Kelly, has pleaded not guilty to one count of racketeering and eight counts of illegally transporting people across state lines for prostitution.

Prosecutors have tried to portray him as an intemperate predator who exploited his fame to attract fans into his circle, where he would demand strict obedience or else punish them.

Kelly has repeatedly denied sexual abuse accusations, which have dogged him for about two decades.

The defence's fifth witness, music industry executive Julius Darrington, testified on Wednesday that he sometimes spent 10- to 12-hour days with Kelly after meeting him in 2016.

Darrington said he never saw women being locked in rooms, heard screaming or crying, or saw Kelly strike anyone, which other witnesses have said took place.

On cross-examination, prosecutor Elizabeth Geddes tried to emphasise how Darrington was not monitoring Kelly around the clock.

"You have no knowledge of what the defendant did behind closed doors when you weren't there, correct?" she asked.

"Correct," Darrington responded.

Kelly also faces separate criminal charges in federal court in Chicago, and state charges in Illinois and Minnesota.