Michael Jackson claimed the spotlight again Thursday even before an expected announcement that he is to stage his first concerts since his infamous child abuse trial four years ago.
Amid reports that he could make tens of millions of dollars from a string of London concerts this year, Jackson is to appear at the giant O2 Arena to announce his plans.
Promoters AEG Live have not given details of what will be revealed at the 1600 GMT news conference.
A source close to the promoters told AFP last month that 50-year-old Jackson was in talks to perform up to 30 London shows this year -- his first major tour for over a decade.
The Evening Standard reported Wednesday that up to 50 concerts could be scheduled at the 20,000-seat O2 Arena in June and July, in a deal with AEG worth more than 100 million pounds.
Some reports have suggested Jackson could be planning the comeback to help pay off multi-million dollar debts incurred since the collapse of the abuse trial against him in 2005.
If confirmed, the concerts would be a spectacular return for Jackson, who dominated the pop world with hit albums like "Thriller" and "Bad" in the 1980s but has virtually vanished from public view since his trial.
Jackson is reportedly close to completing his first new album since 2001, and has collaborated with the new stars dominating the music world such as Kanye West.
But he has been dogged by rumours of ill health, and bookmakers William Hill are already offering 5-1 odds that, should the London concerts go ahead, he will not turn up on the first night.
In November, Jackson was due to appear in court in London as part of a legal dispute but his lawyers said he was suffering from an unspecified medical condition and might not be able to attend. The dispute was settled out of court.
However, the Daily Mirror tabloid reported Thursday that Jackson had passed 50 health tests set by insurers to prove he was fit enough to perform.
The 02 Arena, which is in the giant former Millennium Dome in east London, played host to 21 sellout concerts by Prince in 2007.
Jackson last performed in Britain at the 2006 World Music Awards, where he sang a few lines of "We Are The World". His last official tour was the 1996-7 HIStory World Tour, although he has played one-off gigs since.
The singer became a phenomenally successful star, first with the Jackson Five alongside his brothers and then as a solo artist.
His fame led him to withdraw into a private world at his Neverland ranch in California and he underwent a physical transformation, his skin lightening and his face showing signs of plastic surgery. He has denied undergoing cosmetic surgery.
But Jackson's career hit trouble in 1993 when a 13-year-old boy made sex abuse allegations against him and prosecutors and police launched an investigation.
A year later, Jackson reached an out-of-court settlement with the boy's family, paying out 23.3 million dollars and the criminal case was dramatically stopped. Jackson says he now regrets the payment.
At the same time as Thursday's London announcement, an exclusive preview of Jackson's personal treasures was to go on show in Ireland, ahead of an auction of his belongings from his Neverland ranch.
The display, the only such viewing in Europe, includes an iconic white-jewelled glove and a selection of his on-stage costumes, and fedoras from the video for the hit "Billie Jean".