From Elvis Presley to Princess Diana, iconic funerals are often marked by massive crowds, celebrity mourners and gut-wrenching emotion - and Michael Jackson's memorial will be no different.

More than one million people are expected to pay homage to the King of Pop at his funeral, an event which could dwarf the memorial services held for Presley in 1977 and Diana 20 years later, experts say.

Plans for Jackson's memorial began to filter out, with reports saying the tragic icon would make a poignant return by motorcade to his Neverland fantasy ranch on Thursday.

A public viewing of Jackson's body is planned for Friday before private services for his family take place at the weekend. Precise details of Jackson's burial and final resting place are not known.

Yet intense anticipation has already begun to build, with speculation that the Jackson family could hold a series of simultaneous services in all corners of the globe to reflect the star's huge worldwide appeal.

"Potentially this could be enormous," Robert Thompson, an expert in pop culture at Syracuse University in New York. "Everything that has to do with Michael Jackson was done huge, super-sized.

"Diana was princess of the United Kingdom, so certain limits are placed. For Michael Jackson there are no real rules, everything is possible."

Diana's funeral in 1997 saw unprecedented scenes. Hundreds of thousands crowded into London's Hyde Park to watch a broadcast from Westminster Abbey, where mourners included Hillary Clinton, George Michael and Steven Spielberg.

A further one million people were estimated to have lined the streets as the funeral cortege bearing Diana's coffin wound its way from London to her family's ancestral home.

For Elvis Presley, who died in 1977 at the age of 42, an estimated 80,000 fans descended on Memphis, Tennessee to pay emotional homage to "The King of Rock N' Roll" before his burial at Graceland.

More than 30 years later, an estimated half a million people visit Graceland every year to salute the King, who remains the highest-earning dead celebrity according to Forbes.

However, Thompson noted, the death of Elvis occurred "before 24 hours news, no distribution possibilities, no globalisation."

"Here, the potential distribution is huge," Thompson told AFP.

Reverend Al Sharpton, who has been advising the Jackson family on funeral arrangements said the family wanted to honour both Jackson's superstar impact and his humble roots as the son of a steelworker in Gary, Indiana.

"It is the determination of the family to be careful and deliberate on how they plan his celebration of life because we're talking about a historic figure that really changed pop culture around the world," Sharpton said.

"This is not something you do carelessly and spontaneously."

Thompson said any Jackson funeral would seek to "solidify the story and frame the legacy" of Jackson.

"Michael Jackson's legacy is more than just music," Thompson said. "(He) really matters in lots of issues, not only entertainment.

"Michael Jackson is important for the race issue, it is an enormous cultural power. He stole the crown of Elvis and brought it back."