F1 ACE Jenson Button has claimed Richard Branson drunkenly flirted with his girlfriend during a meal at a posh restaurant.
The champion driver wrote that a "very, very drunk" Branson even touched Japanese model Jessica Michibata's face.
The shock claim, published today in an extract from his autobiography serialised in The Telegraph, levelled grim accusations against the Virgin billionaire.
Button wrote that Sir Richard's behaviour amounted to "blatant flirting" and he "put his hand on (Jessica's) face" during a meal in the Michelin-starred Nobu in Melbourne while in town for the 2009 Australian Grand Prix.
But the McLaren-Honda driver, 37, said tousle-haired Branson later apologised - and pledged to kick booze "for months".
Button wrote that he had gone to the bathroom and returned to find Branson with his hands on Jessica.
"'Hold on,' I said, 'that's enough. That's well out of order.' But he was so hammered that he simply didn't understand what the problem was", Button wrote.
Addressing the incident in his own autobiography Finding My Virginity, Branson wrote: "Jenson and his girlfriend were sitting at the next table, enjoying a far quieter evening as he had to race the next morning,
"By contrast, through a mixture of tiredness, jet lag and drink, I soon found myself very, very inebriated,
"This wasn't like me; I can't remember ever getting that drunk before or since."
He admitted telling Jessica, 32, "how gorgeous she was", adding: "Jenson understandably took offence and I decided to retreat quickly from the table (thankfully, we smoothed it out)."
Jenson and Jessica went on to marry in December 2014 after he proposed with a ring worth £250,000.
But they split a year later on good terms and remain friends, a spokesman said at the time.
The Brit racing star, who won the 2009 Drivers Championship, is now dating former playboy model Brittny Ward, 25.
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