Representatives of multiple faiths have been invited to Friday's ceremony in Louisville, Kentucky
Actor Will Smith and British boxer Lennox Lewis are to carry Muhammad Ali's coffin at his funeral on Friday, it has been announced.
The Hollywood star, who was nominated for an Academy Award and a Golden Globe for his portrayal of Ali in the 2001 film of the same name, will be among eight pallbearers at the boxing legend's funeral.
Carrying the coffin alongside Smith and Lennox - Britain's former world heavyweight champion - will be Ali's cousins John Grady and Jan Wadell, nephew Ibn Ali, former brother-in-law Komawi Ali and family friend John Ramsey.
Among those also named was Jerry Ellis, the brother of Jimmy Ellis, Ali's former sparring partner and fellow world heavyweight champion.
Thousands are expected to turn out for the public memorial in Ali's hometown of Louisville, Kentucky later this week.
The president of Turkey and the king of Jordan will be among speakers, while former US president Bill Clinton will deliver a eulogy, according to organisers.
His widow, Lonnie Ali, daughter Maryum Ali and comedian Billy Crystal will also address the service for the three-time world heavyweight champion, who died last Friday aged 74.
The guest list is likely to mean security will be extra tight for the star-studded memorial.
Ali's coffin arrived in Louisville on Sunday aboard a private plane, accompanied by his wife and other relatives.
On the morning of the funeral, the casket will be paraded through the streets of Louisville, so fans from around the world can say goodbye.
California imam Zaid Shakir will preside over the ceremony, in line with Muslim tradition.
Representatives of multiple faiths have been invited.
Ali will then be buried at a cemetery in Louisville.
On the eve of the ceremony there will be an Islamic prayer service and private family funeral, organisers said.
Islamic studies scholar Timothy Gianotti told reporters in Louisville the funeral "was really designed and intended by the champ himself to be his last statement to the people of planet Earth".
Family spokesman Bob Gunnell said: "He wanted the memorial service to reflect his life and how he lived.
"He wanted everyone to be able to attend.
"He was the people's champ and so he wanted that memorial service to reflect that."
The official cause of Ali's death was septic shock due to unspecified natural causes, though his health problems were complicated by a long battle with Parkinson's disease.
Ali's daughter Laila who followed in his footsteps into the boxing ring, told ABC's Good Morning America on Monday: "I'm obviously really sad.
"But I have been sad for a long time, just watching my father struggling with Parkinson's disease. I have comfort in knowing that he's not suffering anymore."
Meanwhile, Clare County Council is opening a Book of Condolence this morning for the boxing legend.
The three-time World Heavyweight Champion was named the first Honorary Freeman of Ennis when he visited the town in 2009 to celebrate his ancestral links to the area.
Mayor of Ennis, Councillor Pat Daly, says people in the town are devastated.
He says Ali's visit was a "fantastic occasion. 30,000 people came to Ennis, and the whole day was exciting".