Former world No. 1 Dustin Johnson quits PGA tour

Former world number one golfer Dustin Johnson confirmed on Tuesday he has resigned his membership of the US PGA Tour to play in the breakaway LIV Golf Invitational Series.

The decision effectively rules the US two-time major winner out of participating in the Ryder Cup, which pits the United States against Europe.

Johnson was speaking at a press conference at Centurion Club, near London, ahead of the opening event of the Saudi-backed breakaway tour, which starts on Thursday.

The world number 15 said in February he was committed to playing on the PGA Tour, which has refused releases for members to play in LIV Golf's opener.

But he has now quit, following a similar decision by veteran US golfer Kevin Na, who is also in the field for the event in St Albans.

Six-time major winner Phil Mickelson confirmed on Monday he has also signed up to play in a major coup for the organisers.

"I'm very thankful to the PGA Tour and everything that it's done for me... but this is something I felt was best for me and my family and I'm very excited about playing," said Johnson.

The 37-year-old said it was difficult to predict the consequences of his decision to play in the breakaway series.

"Right now, I've resigned my membership from the Tour," he added.

"I'm going to play here for now and that's the plan.

"The Ryder Cup is unbelievable and has definitely meant a lot to me," said Johnson, who won all five of his matches in the United States' record 19-9 win over Europe at Whistling Straits last year.

"Hopefully I will get a chance to do that again, but I don't make the rules."

The former Masters and US Open champion said he was exempt to play in the majors due to his record.

Graeme McDowell, whose Ryder Cup eligibility is tied to membership of the DP