Fresh unverified footage of Peng Shuai was posted online by a state-affiliated journalist on Sunday as international concern persists for the Chinese tennis star after she publicly accused a former vice-premier of forcing her to have sex.

Qingqing Chen, a reporter for the state-owned Global Times, tweeted a video of Peng appearing to speak with Chinese basketball icon Yao Ming.

Chen said the video was sent to her by a "friend" and that it was taken at an event to promote cross-country skiing in Shanghai.

The seven-second clip shows the tennis player smiling and listening as Yao speaks indistinctly.

Chen also posted a photo of Peng posing with Yao and two other Chinese sports figures -- Olympic sailing champion Xu Lijia and retired table tennis player Wang Liqin.

The foursome were standing next to a banner for the "FIS Cross-Country Skiing China City Tour" with Shanghai's Yangpu bridge in the background.

The Shanghai stop of the cross-country ski tour took place on Saturday, according to the state-run CGTN news site.

Twitter is blocked in China and only people with a VPN-type workaround can access it.

Peng Shuai is a former Wimbledon and French Open doubles champion
Peng Shuai is a former Wimbledon and French Open doubles champion AFP / Eric Feferberg

However, many Chinese diplomats and official state media have accounts to defend China's point of view.

Peng, a former Wimbledon and French Open doubles champion, took to Chinese social media in early November to allege that former vice-premier Zhang Gaoli -- who is in his 70s -- forced her into sex during an on-off relationship spanning several years.

Her message was quickly scrubbed from the Chinese web, but not before screenshots were posted on Twitter, sparking a worldwide outcry.

The Women's Tennis Association has called for Peng's allegations to be investigated fully and transparently.

The sporting body announced earlier this month that it was suspending all tournaments in China, including Hong Kong, over concerns about Peng's safety.

State media have previously published other images of Peng at a Beijing tennis tournament as well as a screenshot of an email allegedly written by the player saying "everything is fine".

Peng also participated in late November in a 30-minute video call with Thomas Bach, head of the International Olympic Committee.

But the WTA and fellow tennis players have continued to call for more transparency from Beijing over Peng's whereabouts.