9:00 AM PT -- Howard Weitzman, the attorney for MJ's estate, tells TMZ, “Mr. Robson has adamantly denied under oath and in numerous interviews over the past 20 years that Michael Jackson ever did anything inappropriate to him. He now wants us to believe that he committed perjury at least twice and has been lying to anyone and everyone about Mr. Jackson since the early ‘90s so he can file a claim for money. Mr. Robson’s transparent lawsuit comes nearly 4 years after Michael passed. His claim is outrageous and sad.”
Wade Robson says the only reason he's now changing his story ... accusing Michael Jackson of sexually abusing him for 7 years is because Michael engaged in a campaign of manipulation to keep him silent, especially during MJ's 2005 child molestation trial.
Robson went on NBC Today and said, Michael "performed sexual acts on me and forced me to perform sexual acts on him" from the age of 7 ... until Robson was 14.
Robson claimed he testified in 2005 that Michael did NOT sexually abuse him because Michael told him what they were doing was "an expression of love" ... and added, "if you ever tell anyone what we're doing both of our lives and our careers will be over."
TMZ broke the story ... Robson filed a creditor's claim against Michael Jackson's estate last week, insisting MJ sexually abused him during his childhood for years, but according to sources he didn't take action until he saw a therapist following a nervous breakdown.
Robson referenced the breakdown on Today, saying ... "For the first time in my life I began to realize that my completely numb and unexplored feelings in relation to what Michael did to me might be a problem and maybe I need to speak to someone about it."
Interestingly, Robson denied repressing memories of the alleged abuse ... instead saying he was merely "psychologically and emotionally completely unable and unwilling to understand that it was sexual abuse."
Robson added he doesn't excuse the alleged abuse, but he believed Michael was a "troubled man" who was an amazing talent, but "also a pedophile."
Michael Jackson's estate has told TMZ Robson's allegations are an "outrageous and pathetic" money grab.