The Desert Sun in Palm Springs, California, reported The American Express no longer will have the Phil and Amy Mickelson Foundation as its main charitable arm, and that Mickelson no longer will be the tournament host.

The PGA Tour said it would have no further comment except to confirm Mickelson is no longer involved in its The American Express tournament.

The move comes after the release of part of Alan Shipnuck’s unauthorised biography of the six-time major winner where Mickelson said in an interview that despite believing that Saudi Arabia was guilty of human rights abuses, he sought to use the breakaway league as leverage in his efforts to change the PGA Tour.

"The PGA Tour said it would have no further comment except to confirm Mickelson is no longer involved in its The American Express tournament."

Saudi Arabia's government denies accusations of human rights abuses.

Mickelson's comments drew immediate backlash from golfers including Rory McIlroy and Justin Thomas.

The rival league suffered a big blow last week when none of the top 12 players in the world indicated an interest in joining for guaranteed riches.

The 51-year-old Mickelson offered an awkward statement Tuesday in which he conceded his comments were "reckless" but not meant to be shared.

He also apologised to Greg Norman's LIV Golf Investments for anything taken out of context and referred to them as visionaries who, like him, want to make golf better.

Mickelson did not mention the PGA Tour or Commissioner Jay Monahan, which he referred to in the Shipnuck interview as a "dictatorship".

He said he "desperately needs" time away to get his priorities in order.

KPMG was the first organisation to announce it was immediately ending its corporate sponsorship with Mickelson while Amstel Light also said it was ending its partnership with the left hander.

Callaway Golf, which Mickelson has represented since the 2004 Ryder Cup at Oakland Hills, said it was pausing its relationship.

The company told American publication Golf Digest it was "very disappointed in his choice of words – they in no way reflect Callaway's values or what we stand for as a company".

Workday, which has sponsored Mickelson since 2017, told Golf Digest it would not be renewing the contract when it expires at the end of March.