The WTA announced its decision on Wednesday, concerned that the Chinese player Peng made a sexual assault accusation against a former high-ranking government official and has since disappeared from public view.

Foreign ministry spokesman Wang Wenbin did not directly mention the WTA on Thursday but pointedly said that China "opposes the politicisation of sports".

In an editorial, the Global Times newspaper, published by the ruling Communist Party's People's Daily, said the WTA was betraying the Olympic spirit and bringing politics into tennis.

"Some forces in the West are instigating a boycott against the Beijing 2022 Winter Olympics," it added, referring to the February event which some rights groups want boycotted over China's human rights record.

Peng, a former world No. 1 doubles player, was unseen in public for nearly three weeks after she posted a message on social media in early November accusing China's former Vice-Premier Zhang Gaoli of forcing her into sex.

Neither Zhang, who retired in 2018, nor the government have commented on Peng's accusation and the topic has been blocked on China's heavily-censored internet.

Peng, a three-time Olympian, did appear in mid-November at a dinner with friends and a children's tennis tournament in Beijing, photographs and videos published by Chinese state media and by the tournament's organisers showed.

And the International Olympic Committee (IOC) said it had held a second video call with the 35-year-old player on Wednesday following one late last month.

The IOC said it had offered her support, would stay in regular touch, and had agreed a personal meeting in January.

She appeared to be "safe and well, given the difficult situation she is in", it added in its statement on Thursday.

Unconvinced, however, the US-based WTA wants further assurances of her well-being and an investigation before it returns to the lucrative Chinese market.

"While we now know where Peng is, I have serious doubts that she is free, safe, and not subject to censorship, coercion, and intimidation," chief executive Steve Simon said, suggesting she was pressured to retract her allegation.

Equality for women would suffer a setback if powerful people could suppress accusations of assault, he added. "I am also greatly concerned about the risks that all of our players and staff could face if we were to hold events in China in 2022."

From former women's greats Billie Jean King and Martina Navratilova to men's No. 1 Novak Djokovic, many in the tennis world have applauded the WTA, which stands to lose hundreds of millions of dollars in TV and sponsorship revenue.

"Really strong stance. Far bigger things in the world than a game of tennis," said Australian player John Millman.

Meanwhile, the ATP, the men's tour organisers, and the ITF, the global governing body, also expressed concern for Peng but stopped short of joining the WTA in suspending their tournaments in China.

ATP chairman Andrea Gaudenzi said: "The situation involving Peng Shuai continues to raise serious concerns within and beyond our sport. The response to those concerns has so far fallen short.

"We will continue to consult with our members and monitor any developments as this issue evolves."

The ITF said Peng's allegations must be addressed.

"Our primary concern remains Peng Shuai's well-being ... We will continue to support all efforts being made to that end, both publicly and behind the scenes."

Australian Associated Press