Greg Norman has hit out at the PGA Tour's decision not to grant players permission to contest next month's first LIV Golf Invitational Series event, labelling it "anti-fan and anti-golfer".
Phil Mickelson and Lee Westwood are among the players known to have asked for the required release to play the 54-hole event at Centurion Club, which boasts a total prize fund of $25 million ($A36 million) and offers $4 million ($A5.7 million) to the winner.
However, PGA Tour members were informed on Tuesday releases will not be granted, leaving them open to sanctions if they do tee it up in St Albans from June 9-11.
In a statement, LIV Golf CEO Norman said: "Sadly, the PGA Tour seems intent on denying professional golfers their right to play golf, unless it's exclusively in a PGA Tour tournament.
"The Tour is intent on perpetuating its illegal monopoly of what should be a free and open market. The Tour's action is anti-golfer, anti-fan and anti-competitive." - Greg Norman.
"This is particularly disappointing in light of the Tour's non-profit status, where its mission is purportedly 'to promote the common interests of professional tournament golfers.'
"Instead, the Tour is intent on perpetuating its illegal monopoly of what should be a free and open market. The Tour's action is anti-golfer, anti-fan and anti-competitive.
"But no matter what obstacles the PGA Tour puts in our way, we will not be stopped. We will continue to give players options that promote the great game of golf globally."
Releases were granted for the Saudi International earlier this year, but that is an event previously staged by the DP World Tour and now sanctioned by the Asian Tour.
The LIV Golf events will be seen as a potential rival Tour, with Norman saying on Monday he has been given an extra $2 billion ($A2.8 billion) in funding from Saudi Arabia's Public Investment Fund to build the series of eight events into a full 14-event league by 2024.
Given the strategic alliance between the circuits, it appears likely the DP World Tour will follow the PGA Tour in refusing releases for an event held close to its headquarters at Wentworth.
The decision increases the likelihood of a court battle between the Tour and LIV Golf or individual players.