Jermaine Jackson said on Thursday he hoped R&B star Mary J. Blige would perform at the concert he planned to stage later this month in memory of his brother Michael, but the line-up was still being checked.
Jackson and organizers attempted to play down the lack of confirmed big names for the concert in front of Vienna's Schoenbrunn castle -- with an expected audience of 65,000.
I spoke to them (Blige's personnel) and they very, very much want to do this and they are trying to work out and fix up a commitment they have with Gucci, Jackson told a news conference in Berlin.
Blige is set to be busy at a fashion event in Italy on the day of the concert.
The star is Michael Jackson -- it's not about name dropping and who else will be there, the show's producer Georg Kindel said.
The organizers plan to announce a list of confirmed acts at a further news conference in Vienna next week after Jackson has personally confirmed the stars' attendance.
It seems that there is a lot of confusion regarding the confirmed talent for the tribute -- we are rechecking and confirming each artist personally, Kindel said.
Organizers had previously listed stars including Akon, R&B artist Chris Brown and veterans Natalie Cole and Sister Sledge as on board to reinterpret Jackson's greatest hits including Billie Jean, Thriller and Bad.
The singers will be supported by the band and dancers who were to accompany Jackson on his planned This Is It series of comeback concerts before the superstar died from a drug overdose on June 25.
Michael Jackson's mother Katherine also pledged her support for the concert in a video message played to the news conference in an effort to allay rumors of a family feud surrounding the tribute.
I am looking forward to being there, she said in a video recorded at around midnight on Wednesday in the library of the Jackson family compound in Los Angeles. I am sure it is going to be a great show.
Negotiations are taking place with more than 50 TV networks to broadcast the spectacle to fans worldwide, Kindel said.
Tickets for the concert -- where Jermaine Jackson also plans to perform a planned medley of Jackson Five hits -- are being sold in stages for 63 to 518 euros ($92-$755).
In 2002 Michael Jackson caused outrage in Berlin after he dangled his baby son out of a fourth-floor window of a five star hotel in front of hundreds of fans.