UPDATE 1-Jackson memorial likely Tuesday, Rowe wants custody

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LOS ANGELES, July 2 (Reuters) - A public memorial for Michael Jackson is expected to be held on Tuesday in Los Angeles, a concert promoter said on Thursday, as the singer's former wife said she planned to fight for custody of their children.

Randy Phillips, chief executive of concert promoter AEG Live, said Jackson's highly anticipated memorial was being planned for a rock concert and sporting venue, the Staples Center, in Downtown Los Angeles. Jackson, 50, died a week ago of cardiac arrest.

Phillips told reporters the memorial would probably be held on Tuesday, although the date had not been finally confirmed by Jackson's family.

"They (the family) want to have it at Staples Center. The question is when," Phillips said.

He said details of the form the memorial in the 20,000- seat indoor arena will take were still being discussed.

Meanwhile Debbie Rowe, the mother of Jackson's two eldest children, told NBC4 television in Los Angeles she would seek custody of the kids, setting the stage for a legal tussle with Jackson's parents.

"I want my children," Rowe said in a telephone interview with NBC4.

Temporary guardianship was granted earlier this week to Jackson's mother, Katherine. A 2002 will signed by Jackson specifically cut Rowe out of his estate and asked that the children be cared for by his mother. (Reporting by Alex Dobuzinskis)