'Never OK': Naomi Osaka 'in shock' over Peng Shuai situation

Naomi Osaka has expressed her shock and concern over the Peng Shuai situation, amid reports the Chinese tennis star has disappeared after levelling sexual assault allegations against one of the country's top former officials.

Peng, 35, posted a message on Chinese social media outlet Weibo on November 2 that accused retired Chinese Vice Premier Zhang Gaoli of sexual assault.

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The message was removed within an hour of being posted, and mentions of the allegation have since been scrubbed from Chinese internet under control of the nation's government.

Peng alleged that Gaoli, who became a member of the Politburo Standing Committee - China's top decision-making body - forced her into having sex despite repeated refusals following a round of tennis three years ago.

Her post also said they had sex once seven years ago and she had feelings for him after that.

Peng, who's won doubles titles at Wimbledon and the French Open, hasn't been seen in public since levelling the accusation, prompting concerns in the tennis and activist communities about her safety.

After learning of the situation, Osaka posted a message of concern for Peng on social media, in which she hit out against censorship in any form.

"I was recently informed of a fellow tennis player that has gone missing shortly after revealing that she has been sexually abused," Osaka wrote.

"Censorship is never ok at any cost, I hope Peng Shuai and her family are safe and ok. I'm in shock of the current situation and I'm sending love and light her way."

Osaka's message was accompanied with the hashtag #WhereisPengShuai to raise awareness about Peng's plight.

The Chinese government declined to address the subject until Monday when foreign ministry spokesman Zhao Lijian was asked about it at a news conference.

He claimed that he wasn't aware of Peng's situation before shutting down further questioning on the subject.

"I have not heard of the issue you raised," Zhao told reporters. "This is not a diplomatic question."

He didn't address Peng's status or her accusation beyond that response.

The WTA has attempted to allay fears Chinese tennis star Peng Shuai is in danger after her sexual assault allegations against a now Chinese Ruling Party member, after World No.1 Novak Djokovic also expressed his shock at the situation.

WTA allays fears over Peng Shuai's safety

WTA director Steve Simon said they had received assurances Peng is safe in Beijing, despite revealing he had not "spoken directly with her."

'We've received confirmation from several sources, including the Chinese Tennis Association, that she is safe and not under any physical threat," Simons said in a statement to the New York Times, according to AFP.

"My understanding is that she is in Beijing in China, but I can’t confirm that because I haven’t spoken directly with her."

It comes after the tennis community rallied around Peng, with Djokovic among those to express his shock over the situation.

"I don't have much information about it, I did hear about it a week ago, and honestly it's shocking that she's missing," Djokovic said.

"More so that it's someone that I've seen on the tour in previous years quite a few times."

Djokovic, is playing in the season-ending ATP Finals in Italy, said he was thinking of her family during these difficult times.

"There's not much more to say than to hope that she's okay and it's just terrible," the World No.1 added.

"I can imagine how her family feels, you know, that she's missing."

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