According to witnesses, Mr Singleton and Mr Cowin had been lunching together with musician Jon Stevens.

The lunch party arrived at Kingsleys at 1pm. It was after 4pm when onlookers saw Mr Singleton lunge at Mr Cowin, with staff at the restaurant attempting to separate the men.

"It looked like John was going after Jack. Jack was still sitting down and Singo was standing over him. We could see Jack was pushing him away. Singo really lost it, I think everyone was pretty shocked by what they saw," a witness to the fracas told PS.

Mr Singleton, Mr Cowin and Stevens were filmed leaving the restaurant late in the afternoon with two other men. The footage ends bizarrely when Mr Singleton runs at at the cameraman yelling that he loves violence.

Footage shown on Channel Nine shows the cameraman initially quizzing Mr Singleton about the stoush in the restaurant, asking: "Was that just a bit of fun between friends then, or what was the story?"

A smiling Mr Singleton responds: "Nah it was a f---ing fight."

Asked what the fight was over, Mr Singleton said it was "over a woman", although when asked to specify which woman, he said: "We don't have one."

The cameraman then asks Stevens what is his view on violence.

Stevens: "It sucks."

Mr Singleton: "Oh we love it, we love it, we love it."

Stevens: "He loves it, I don't."

Mr Singleton then begins running towards the cameraman, yelling: "Oh I do, I f---ing love it, I f---ing love it, I f---ing love it!"

He is shown chuckling afterwards, and says: "You've got to be kidding".

Following the fracas, Mr Singleton and Stevens adjourned to the nearby Bells Hotel, with Stevens and another unidentified man carrying the millionaire across Cowper Wharf Road.

They were seen "propped up at the bar" drinking beer. Mr Singleton was later seen leaving the hotel at 6.45pm when his chauffeur-driven limousine collected him. Mr Cowin was not seen following the lunch.

It is understood The Daily Telegraph purchased a set of photographs showing the incident for about $10,000 and published them on Tuesday morning.

Comment is being sought from Mr Singleton, who was later seen leaving the restaurant being supported by Stevens, the former fiance of Jodhi Meares who most recently was in the news over domestic violence charges that were later dropped.

Mr Cowin's net worth was estimated at $940 million in 2014 by BRW magazine. He is a majority shareholder in Competitive Foods Australia, which operates the Australian Burger King franchise under the Hungry Jack's banner. He also has significant investments in Domino's Australia and Domino's USA. He also sits on the board of Fairfax Media, which publishes smh.com.au.

Mr Singleton was estimated to be worth $370 million by BRW last year and has pioneered a media and marketing empire. In March shareholders in Mr Singleton's Macquarie Radio Group voted in favour of a $200 million merger with Fairfax Media's radio division.

Mr Singleton and Mr Cowin have been described as long term friends and business associates. Indeed, Mr Singleton's former advertising agency handled many of Mr Cowin's advertising accounts.

With Megan Levy