The president of Aeg Live screamed at Michael Jackson and slapped him "on the butt" when he discovered the superstar was "drunk and despondent" shortly before he was due to announce his comeback shows.

Randy Phillips, head of the concert promotion company, has been testifying in court in Los Angeles as part of the ongoing wrongful death lawsuit filed against the firm by the King of Pop's mother, Katherine Jackson.

Last week (ends09Jun13), Phillips took the stand to talk about the press conference at London's O2 Arena in March, 2009 when Jackson announced he would be staging a massive 50-gig residency at the venue.

The event was held just months before Jackson's death from an accidental drug overdose in June, 2009, and Phillips has revealed he was furious when he discovered the Thriller star was intoxicated before he was due to hit the stage to address the press.

In emails unveiled in court, Phillips told his boss he went to see Jackson in his hotel suite and had to help manager Tohme Tohme get the drunk star dressed and ready for the event, writing, "Mj (Jackson) is locked in his room drunk and despondent. Tohme and I are trying to sober him up and get him to the press conference with his hair/makeup artist... I screamed at him so loud the walls were shaking. Tohme and I have dressed him, and they are finishing his hair, and then we are rushing to the O2. This is the scariest thing I have ever seen. He's an emotionally paralysed mess, filled with self-loathing and doubt now that it is show time. He is scared to death. Right now I just want to get through this press conference."

In the emails, Phillips also claimed he slapped Jackson and forced him into a cold shower to sober him up, although the businessman insisted in court that his words were an exaggeration, saying, "(It was a) very tense situation (and) frankly, I created the tension in that room. Because I was so nerve-racked, Ok, the time (was) slipping away, and his career slipping away... I slapped him on the butt."

Jackson's mother brought the lawsuit claiming Aeg bosses should take responsibility for hiring Dr. Conrad Murray, the medic who administered the fatal drug dose which killed the star and who is now serving a prison sentence for involuntary manslaughter.

Aeg chiefs are fighting the claims and Phillips is expected to resume his testimony on Monday (10Jun13).