Players who have joined the Saudi-backed LIV Golf Invitational Series will not be allowed to "freeride" off the PGA Tour, commissioner Jay Monahan said on Sunday.
Monahan spoke to CBS host Jim Nantz during the network's coverage of the final round of the RBC Canadian Open, three days after suspending PGA Tour members who teed off in the inaugural LIV Golf event at Centurion Club, despite having been refused permission.
Asked why players could not do both, Monahan said: "I guess I would answer the question by asking a question - 'Why do they need us so badly?"'
"Those players have chosen to sign multi-year lucrative contracts to play in a series of exhibition matches against the same players over and over again."
Monahan said that the best players in the game were competing in Canada and that "true competition creates the profile of the world's greatest players".
He added: "In protecting our loyal members, we can't allow (LIV Golf) players to freeride off that."
Monahan was also asked about the letter sent by a group representing victims' families and survivors of the 2001 terrorist attacks in the United States to representatives of Phil Mickelson, Dustin Johnson, Bryson DeChambeau, Patrick Reed and Kevin Na.
The letter accuses the players of sportswashing and betraying their country, highlighting that "Osama bin Laden and 15 of the 19 September 11 hijackers were Saudis."
"I think you'd have to be living under a rock to not know there are significant implications. Two families close to me lost loved ones," Monahan said.
"I would ask any player that has left, or any player that would ever consider leaving, have you ever had to apologise for being a member of the PGA Tour?"