Jackson, like Floyd, is from Houston where both were star high school athletes in the 1990s. He and Floyd called each other "twin" because of their resemblance.
The handcuffed black man died after pleading for air as a white Minneapolis police officer knelt on his neck.
That officer, Derek Chauvin, was arrested on Saturday and charged with third-degree murder and manslaughter. The charges were announced shortly after Jackson spoke at a news conference organised by activists at Minneapolis City Hall. Actor Jamie Foxx and Minnesota Timberwolves star Karl-Anthony Towns were among those in attendance.
READ MORE:
• George Floyd killing: Accused police officer opened fire on 2 people
• George Floyd killing: Minneapolis cop charged with murder after kneeling on neck
• George Floyd killing: Transcript of 911 call that sparked his arrest released
• George Floyd death: Second night of protests, mayor calls for National Guard
Jackson is 42. He played for eight NBA teams from 2000-2013 and won a championship in 2003 with the San Antonio Spurs.
Fellow basetballer LeBron James posted a tribute to Floyd, of himself wearing a black T-shirt with the words "I can't breathe" on it – what Floyd repeatedly told the US officer who was kneeling on his neck.
Rising tennis star Coco Gauff also joined the chorus of protest by creating an emotional Tiktok video which references a number of previous high-profile deaths involving US police officers and black members of the public.
"This is why I am using my voice to fight against racism," Gauff's video states. "I am using my voice. Will you use yours?"
Meanwhile, two prominent voices in the NFL have also spoken out with Cincinnati Bengals rookie quarterback Joe Burrow among just a few white US sports stars to make a public statement.
Burrow said that the "black community needs our help" on Twitter.
"They have been unheard for far too long," said Burrow, the Heisman Trophy winner from Louisiana State and No 1 overall pick in last month's NFL draft. "Open your ears, listen, and speak. This isn't politics. This is human rights."
The coach of the Miami Dolphins, Brian Flores, told ESPN athletes have a chance to lead change for the better in US communities.
"I lead a group of young men who have the potential to make a real impact in this world. My message to them and anyone else who wants to listen is that honesty, transparency and empathy go a long way in bringing people together and making change. I hope that the tragedies of the last few weeks will open our hearts and minds to a better way of communicating and hopefully create that change."
Colin Kaepernick, the former San Francisco 49ers quarterback who famously knelt during the national anthem in 2016 to highlight racial injustice also took to Instagram to tell his fans "when civility leads to death, revolting is the only logical reaction".
"We have the right to fight back. Rest in Power George Floyd," he wrote.
- with AP
