In a memo to membership early Thursday, the PGA Tour announced that any current and future players in the LIV Golf Invitational Series are indefinitely suspended.

The announcement came less than a half-hour after the rival league kicked off play Thursday at the Centurion Club outside London, with a 48-man field featuring a handful of PGA Tour stalwarts, including Phil Mickelson, Dustin Johnson and Sergio Garcia.

Commissioner Jay Monahan said that the 17 members competing in the inaugural LIV event are in violation of the Tour’s tournament regulations, since the Tour announced May 10 that it would not grant conflicting-event releases for those interested in the upstart league. Monahan has repeatedly told players that they would face punishment for competing in LIV events without releases.

Any Tour players who compete in future LIV series events – Bryson DeChambeau is among those who have committed to the second event, June 30-July 2 in Oregon – will also be suspended. They will not be eligible to compete in the Presidents Cup this September.

Johnson and Garcia were among those who resigned their tour membership. As a result, their names will be removed from the FedExCup points standings and they will not be allowed to receive sponsor exemptions as a non-member. 

Mickelson, who has lifetime Tour status after winning more than 20 events across 15-plus seasons, said Wednesday that he did not plan to relinquish his membership. Mickelson's agent, Steve Loy of Sportfive, did not have any additional comment on the Tour's suspension.

Of the 17 players who were suspended, only six were currently ranked inside the top 125 in FedExCup points, and just one, Talor Gooch (No. 13), was ranked inside the top 40. Those players also will not be eligible for the Presidents Cup this September; the only member currently in a qualifying position was Louis Oosthuizen, who was ranked fifth in the International standings. 

“These players have made their choice for their own financial-based reasons,” Monahan wrote. “But they can’t demand the same PGA Tour membership benefits, considerations, opportunities and platform as you. That expectations disrespects you, our fans and our partners. You have made a different choice, which is to abide by the tournament regulations you agreed to when you accomplished the dream of earning a PGA Tour card and – more importantly – to compete as part of the preeminent organization in the world of professional golf.”

The full list of players who are suspended: Mickelson, Johnson, Garcia, Gooch, Oosthuizen, Branden Grace, Matt Jones, Martin Kaymer, Graeme McDowell, Kevin Na, Andy Ogletree, Turk Pettit, Ian Poulter, Charl Schwartzel, Hudson Swafford, Peter Uihlein and Lee Westwood.

Shortly after the Tour memo was released, LIV Golf – which is fronted by former world No. 1 Greg Norman and supported by Saudi Arabia's Public Investment Fund – responded with its own statement, calling the Tour's actions "vindictive" and vowing that "this certainly is not the last word on this topic."

“Today’s announcement by the PGA Tour is vindictive and it deepens the divide between the Tour and its members," the statement read. "It’s troubling that the Tour, an organization dedicated to creating opportunities for golfers to play the game, is the entity blocking golfers from playing.  This certainly is not the last word on this topic. The era of free agency is beginning as we are proud to have a full field of players joining us in London, and beyond.”

The London event is the first of seven regular-season tournaments on the LIV schedule, each promising a 54-hole, no-cut event, a shotgun start and a record $25 million purse, with $4 million to the individual winner. The team championship later this fall will offer a $50 million prize fund.