HELSINKI: American rapper A$AP Rocky pleaded not guilty to assault as his trial in Sweden opened Tuesday, a month after a street fight that landed him in jail and became a topic of US-Swedish diplomacy.

Rocky, whose real name is Rakim Mayers, is accused with two others of beating a 19-year-old man in Stockholm on June 30. Prosecutors played video footage in court that showed Mayers throwing a young man to the ground.

Wearing sweatpants and a green T-shirt in court, Mayers, 30, pleaded not guilty to an assault charge that carries a maximum penalty of two years in prison. He says he acted in self-defense.

The Grammy-nominated artist's extended detention prompted US President Donald Trump to personally intervene on his behalf earlier this month. Mayers nevertheless remained behind bars, angering Trump.

Swedish news agency TT said Trump sent the US special presidential envoy for hostage affairs to Stockholm to monitor the court proceedings and to show support for Mayers.

The special envoy, Ambassador Robert O'Brien, was seen at Stockholm District Court in the morning. A biographical statement on the State Department's website says O'Brien "leads the US government's diplomatic efforts on overseas hostage-related matters."

"He works closely with the families of American hostages and advises the senior leadership of the US Government on hostage issues," the website states.

A senior US official in Washington described O'Brien's presence as part of an effort to convey Trump's concern about the case, support American citizens "and, to, hopefully, bring them home." The official spoke on condition of anonymity to The Associated Press because they were not authorized to discuss it by name.

Fellow rapper RZA (RIHZ'-uh) of the Wu-Tang Clan told The Associated Press on Friday he was concerned about A$AP Rocky and "disappointed that a judge cannot discern that this is not a man you hold hostage."

A$AP Rocky's mother, Renee Black, also attended the proceedings. She said beforehand she was convinced her son is not guilty,

"This is a nightmare," Black was quoted by Swedish media as saying.

Prosecutors and defense lawyers presented competing narratives on the trial's opening day of what happened the night of the fight.

Prosecutors said 19-year-old Mustafa Jafari and a friend got into an argument with Mayers and one of his bodyguards near a fast-food restaurant where the rapper's entourage had eaten.

Mayers has published videos on his Instagram account that showed him repeatedly pleading with the two to stop following him and his associates.

Defense lawyer Slobodan Jovicic stressed Tuesday that the rapper and his entourage "didn't want any trouble" and alleged that Jafari and his friend had exhibited "aggressive and deeply provocative behavior."

A$AP Rocky previously encountered violent situations because of his fame and "there are some people who don't always wish him well." Jovicic said.

"He's has been harassed in the past. In this case, the bodyguard made the assessment that these people should move on ... and not to come close," the lawyer said.

Prosecutors alleged in court documents that Mayers and the two other men thought to be part of his entourage beat and kicked Jafari while he was on the ground.

Jafari also was hit with parts of or a whole bottle, they alleged. The court file includes photos of Jafari's cuts, bruises and blood-stained clothes.

Another lawyer representing A$AP Rocky in Sweden, Martin Persson, told public broadcaster SVT he would present evidence showing "no bottle has been used to hit or injure anyone."

Any physical aggression by Mayers and his co-defendants was "within the limits of the law," Persson said.

The trial is expected to continue with witness testimony on Thursday and could run through Friday, Stockholm District Court.

Mayers, along with two men thought to be members of his entourage, was jailed on July 3 and remains in custody.

His case has drawn the attention of American celebrities and Mayers' fellow recording artists, including Sean "Diddy" Combs and Justin Bieber. A social media campaign for his release, #JusticeForRocky, was created soon after his arrest.

Trump also weighed in, asking for a phone call with Swedish Prime Minister Stefan Lofven and offering to personally guarantee A$AP Rocky's bail. The two leaders spoke, and the prime minister's spokeswoman said Lofven stressed he couldn't interfere in a legal case.

Sweden doesn't have a bail system, so Mayers stayed behind bars despite Trump's vouching for him. After prosecutors filed charges Thursday, Trump took to Twitter to criticize Lofven "for being unable to act."

"Give A$AP Rocky his FREEDOM," Trump added. "We do so much for Sweden but it doesn't seem to work the other way around. Sweden should focus on its real crime problem! #FreeRocky."