The FCC said it was made aware of the problem following news reports chronicling how journalists from several media outlets had faced delays in securing visas.

It noted that Washington and Beijing had been embroiled in a tit-for-tat battle – including the expulsion of journalists and cuts to quotas – as tensions between the two nations flared.

The organisation called the Chinese government’s move to target US reporters “unfair and self-defeating”. But it also condemned restrictions the US had placed on Chinese journalists.

“The FCC opposes using journalists’ visas as a weapon in international disputes and also opposes taking action against journalists for the decisions made by their home countries,” it said.

The Post is among media outlets encountering delays amid a resurgence of Covid-19 in recent weeks, which has resulted in tightened social-distancing rules and civil servants being told to work from home.

“The South China Morning Post employs numerous foreign-passport holders and has experienced some delays in the granting of work permits and renewals recently, since the third wave of the coronavirus pandemic hit Hong Kong,” a spokesman for the paper said.

The Post has contacted the Immigration Department and Chief Executive’s Office for comment.

In a late-night response to the FCC’s statement, Beijing’s foreign affairs office in Hong Kong accused the US of “ramping up political suppression” of Chinese media in the country and said the central government had the diplomatic authority to take countermeasures.

A spokesman for the Commissioner’s Office of the Foreign Ministry in Hong Kong said in a statement that China would be compelled to take “necessary and just reactions to safeguard its legitimate rights and interests”. It said the US was solely responsible for the situation and hoped the FCC would “distinguish right from wrong”.

Last month, The New York Times newspaper announced it would move a third of its staff based in Hong Kong to Seoul. The move came after Hong Kong refused to grant its veteran China correspondent Chris Buckley a work permit.

In February, the US government declared that five mainland Chinese media outlets – Xinhua news agency, China Global Television Network (CGTN), China Radio International, China Daily and Hai Tian Development USA – were agencies controlled by Beijing.

Hours later, Beijing expelled three reporters from The Wall Street Journal after the newspaper ran an opinion piece titled “China is the real sick man of Asia”.

The following month the US State Department cut the number of Chinese employees of the five outlets permitted in the country to 100, from 160. Two weeks later, Beijing revoked press credentials for American journalists from The New York Times, The Wall Street Journal and The Washington Post.

Ministry of Foreign Affairs spokesman Wang Wenbin told a daily press briefing in Beijing on Thursday that the US had cut Chinese journalists’ visas to 90 days. And those who had applied for renewals had not heard back.

He accused the US of hypocrisy and vowed to take “necessary and appropriate actions”.

On Monday, Hu Xijin, editor of state-owned newspaper Global Times, noted that the visas had not been renewed and suggested that Beijing could target American journalists based in Hong Kong in retaliation if all Chinese journalists were forced to leave the country.

The body said journalists should be allowed to work without intimidation and obstruction.

Veteran British journalist Victor Mallet of the Financial Times did not have his work visa renewed in 2018 after he moderated a forum held at the FCC featuring pro-independence activist Andy Chan Ho-tin.

Meanwhile, former Hong Kong leader Tung Chee-hwa told a forum on China’s smart court system that the national security law would not affect the rights and freedoms of most Hong Kong people.

Supreme People’s Court vice-president Jiang Wei, who also spoke at the event, echoed his comments.

Additional reporting by Holly Chik and Tony Cheun g