A video was published on social media showing Australian Open staff asking a spectator to remove a t-shirt featuring the message.

Police are seen in the video informing the spectator that the tournament has a rule prohibiting political slogans, which is part of the entry conditions.

Concerns for Peng's welfare have been raised since she made allegations of sexual assault against a high-ranking Chinese Communist Party (CCP) official in early November.

Peng, a two-time Grand Slam doubles champion, has rarely been seen in public since.

Peng last month reportedly retracted the allegations against Zhang Gaoli, a former senior vice-premier and senior CCP official, but there have been concerns raised over the legitimacy of her comments and Peng's ability to speak freely.

Tennis Australia said Peng’s safety was the organisation’s "primary concern", but defended the removal of t-shirts and banners.

"Under our ticket conditions of entry we don't allow clothing, banners or signs that are commercial or political," Tennis Australia told ESPN.

"Peng Shuai's safety is our primary concern.

"We continue to work with the WTA and global tennis community to seek more clarity on her situation and will do everything we can to ensure her wellbeing."

A fundraising campaign has been launched by activists, seeking to produce one thousand shirts which they claim will be given out for free to spectators entering the women's singles final in Melbourne.

The Women's Tennis Association (WTA) and several players have expressed worry for Peng’s welfare in recent weeks, including at the Australian Open.

Four-time Grand Slam winner Naomi Osaka said more information was needed about Peng’s situation, with the former world number one praising the WTA’s handling of the case.

The WTA pulled all events from China in response to the crisis, with the organisation expressing doubts over the veracity of comments attributed to Peng, published by Chinese state media.

The organisation has said it has "significant concerns about her well-being and ability to communicate without censorship or coercion".

WTA Player Council member Victoria Azarenka has said there have been few developments regarding contact with Peng.

The International Olympic Committee (IOC) has had direct contact with Peng, holding two video calls with the three-time Olympian in late 2021.

IOC President Thomas Bach insisted in December that "all aspects of this case are being discussed with the Chinese side", in the face of criticism of the IOC not mentioning the allegation of sexual assault in any of its communications on the matter.

China's Foreign Ministry has accused others of "malicious hyping" and "politicisation" of the Peng case.

It has proved a major controversy in the build-up to the 2022 Winter Olympic Games in Beijing, scheduled to open on February 4.