A$AP Rocky told the court that his life was "unique and particular" (File Photo)

US rapper A$AP Rocky Thursday told a Stockholm court he felt "scared" and had tried to "walk away" before a street brawl, in an assault case that has stirred diplomatic tensions and outraged fans.

The artist faces up to two years in prison over the incident, which saw him and his crew embroiled in a physical fight with a 19-year-old plaintiff in Stockholm on June 30.

The rapper, whose real name is Rakim Mayers, appeared calm as he recounted how he and his entourage had repeatedly told the plaintiff to leave them alone.

"We pleaded, and we begged him," said Mayers who is on trial along with two other people.

He said the plaintiff's behaviour seemed "fearless" and beyond his bodyguard's control. "That's what scared us the most," he said.

The artist also told the court that his life was "unique and particular," and explained that 10 months earlier he had been stabbed in his face by strangers.

Mayers conceded he "threw" the plaintiff to the ground and "kicked his arm", but denied the prosecution's claim that a bottle was used and insisted he only acted after the accuser and his friend began attacking his bodyguard.

The defence has argued Mayers acted out of self-defence and entered a not-guilty plea.

Ahead of Thursday's hearings, dozens of fans joined a sea of reporters and cameras outside the tribunal in Stockholm for a chance to hear the rapper testify. Some supporters pleaded "please, please" for the limited tickets handed out by court security officers.

Mayers' mother Renee Black showed up for the trial's second day wearing a black shirt with the words "A$AP Rocky" printed on the front and back.

The rapper was arrested on July 3 along with three other people following the fight. His bodyguard was later released.

Considered a "flight risk", A$AP Rocky has been held in custody since his arrest.

Video Evidence

Thursday's proceedings started with the defence's cross-examination of the plaintiff.

He has alleged that he was attacked by the rapper and his entourage, when he followed them to ask about a pair of headphones that had broken in an earlier scuffle with the artist's bodyguard.

Mayers' lawyer, Slobodan Jovicic, sparred with the plaintiff and tried to poke holes in his testimony.

Much of the trial has centred around video evidence and whether a bottle had been used as a weapon during the alleged assault.

One video published by US celebrity news outlet TMZ shows the rapper throwing a young man to the ground and apparently aiming several punches at him while he is down.

The court has also seen videos posted to the artist's own Instagram, purporting to show the lead-up to the brawl, which the prosecution argued had been heavily edited.

After the hearing ended on Thursday, Jovicic told reporters he felt things had gone "according to plan," and said the rapper had been able to see his mother the day before.

"He said he was able to hug his mom and that made him really happy," Jovicic said.

The trial is scheduled to conclude on Friday, but judge Per Lennerbrant indicated Thursday that there could be an extension.

Once the hearings conclude, the court has to announce a verdict date and rule on whether the accused should still be detained in the meantime.

#FreeRocky

Fans, fellow artists and US Congress members have been campaigning for his release.

An online petition called #JusticeForRocky has garnered more than 640,000 signatures. Social media campaigns have urged fans to boycott Swedish brands such as IKEA.

US President Donald Trump has repeatedly called for the rapper to be freed, drawing complaints of interference from Swedish politicians.

Robert C. O'Brien, US Special Presidential Envoy for Hostage Affairs, has been sent to attend the trial.

"The president asked me to come here and support these American citizens and we're working to bring them back as soon as possible," O'Brien told AFP on Tuesday.