Four-time Grand Slam champion Naomi Osaka has withdrawn from next month's rescheduled ATP/WTA Indian Wells tournament in California, organisers confirmed Wednesday.

The 23-year-old Japanese star is a former champion at Indian Wells, winning the title in 2018 with victory over Daria Kasatkina.

Osaka said earlier this month she planned to take an indefinite break from tennis after an upset early exit from the US Open.

"I honestly don't know when I'm going to play my next tennis match," Osaka said following her third round defeat to Canadian teen Leylah Fernandez.

"I think I'm going to take a break from playing for a while."

Osaka, who dropped out of the top five in the latest world rankings, has been in the spotlight this year after withdrawing from the French Open and skipping Wimbledon over mental health issues.

Osaka said her problems were exacerbated by speaking to the media after matches.

Osaka had also made an early exit from Cincinnati last month, and had bowed out of the Tokyo Olympics in the early rounds in July.