ASAP Rocky. Picture: Bang Showbiz

A$AP Rocky is designing new uniforms for Swedish prisons after spending a month in jail in Stockholm over the summer.

The 31-year-old rapper spent a month in jail in Stockholm over the summer when he was arrested following a street altercation, and was later found guilty of assault alongside his co-defendants Bladimir Corniel and David Rispers.

But four months after being released from jail on August 2, Rocky will return to the European country for a performance at the Ericsson Globe in Stockholm on December 11 and plans to donate a portion of the proceeds of his concert to prison reform along with designing new uniforms for inmates.

Fredrik Wallin, who runs Kronoberg remand prison where Rocky was held, told Swedish newspaper Aftonbladet that the star's lawyer sent him photos of the new design.

He claims it consists of a green tracksuit with the word "PROMENVD" printed on the chest.

According to Forbes, Rocky said: "When I was going through my whole situation, the whole time I used to look on television and see Swedish fans showing me so much love and I want to give it back.

"I'm trying to do what I can with what I can, I just want to keep creating and encouraging whoever is after me to do it better."

Rocky was taken into custody on July 2 for his involvement in a fight prior to a music festival.

After a high-profile trial, he was found guilty of assault and was ordered to pay R19 265 compensation to his 19-year-old victim, Mustafa Jafari.

Rocky was not given any further jail time after being found guilty - despite prosecutors asking for a six month sentence - because prosecutors could not prove a bottle was used in the attack.

The court said in a statement at the time: "The assault has not been of such a serious nature that a prison sentence must be chosen.

"The defendants are therefore sentenced to conditional sentences."

And the 'Praise the Lord' hitmaker - whose real name is Rakim Mayers - admitted he was "disappointed" by the verdict, but wanted to "keep moving forward".

Posting on Instagram, he wrote: "I AM OF COURSE DISAPPOINTED BY TODAY'S VERDICT. I WANT TO SAY THANKS AGAIN TO ALL OF MY FANS, FRIENDS, AND EVERYONE WHO SHOWED ME LOVE DURING THIS DIFFICULT TIME. IMMA KEEP MOVING FORWARD. THANK YOU TO MY TEAM, MY MANAGEMENT, ATTORNEYS, LABEL AND EVERYONE WHO ADVOCATED FOR JUSTICE. (sic)"