The US on Sunday warned China against interfering with American journalists working in Hong Kong, in an escalating row between the two countries over press freedom and issues like coronavirus, trade among others. The two sides have expelled each other’s reporters in tit-for-tat moves over recent months as they level allegations over the coronavirus pandemic and US President Donald Trump threatens to impose fresh trade tariffs.

“It has recently come to my attention that the Chinese government has threatened to interfere with the work of American journalists in Hong Kong,” US Secretary of State Mike Pompeo said in a statement.

“These journalists are members of a free press, not propaganda cadres.”

Pompeo did not explicitly criticize China, nor did he give specific examples of what he was referring to, but the statement is the latest US response after Beijing expelled more than a dozen American reporters.

“Any decision impinging on Hong Kong’s autonomy and freedoms as guaranteed under the Sino-British Joint Declaration and the Basic Law would inevitably impact our assessment of One Country, Two Systems and the status of the territory,” Pompeo said.

‘One Country, Two Systems’ is the arrangement under which Hong Kong was handed back to China from Britain in 1997, designed to guarantee rights and freedoms in the semi-autonomous city.

In February, China kicked out three journalists from The Wall Street Journal after the newspaper ran an opinion piece on the coronavirus crisis with a headline that Beijing deemed racist.

Weeks later, Washington curbed the number of Chinese nationals from state-run news outlets in the United States.

Beijing responded in March by expelling more than a dozen American journalists from The New York Times, The Washington Post and the Wall Street Journal.

China’s foreign ministry also made the landmark announcement that these journalists would not be allowed to work in Hong Kong, even though the financial hub is nominally in charge of its own immigration policies.

The semi-autonomous financial hub is a major regional base for international media partly because it boasts certain liberties denied on the authoritarian mainland. In the past, foreign journalists expelled from China often relocated to Hong Kong.

The foreign ministry’s decision caused alarm among both media and business groups who fear a new precedent has been set and that international companies in Hong Kong could become hostage to US-China tensions.

Hong Kong’s pro-Beijing government has yet to state clearly whether it has the discretion to allow any of the expelled journalists in — including one of the expelled reporters who is a US citizen with permanent residency status in Hong Kong.