Britain and the United States have called for Hong Kong’s freedoms and “way of life” to be protected in two separate statements ahead of the 20th anniversary of the city’s “handover” to China.

Hong Kong’s achievements are the result of its high degree of autonomy, its economic and personal freedoms, and its respect for rule of law, the US Department of State said in a statement.

“The United States remains concerned about any infringements of civil liberties in Hong Kong, including intrusions on press freedoms… As Hong Kong looks ahead to its third decade under Chinese sovereignty, we urge the preservation and enhancement of the key values and traditions that had made the city such an enviable success.”

Meanwhile, Britain’s Foreign Secretary, Boris Johnson, gave a statement that made reference to the Sino-British Joint Declaration of 1984, in which the principle of “once country, two systems” for a post-handover Hong Kong was enshrined.

“The rule of law, an independent judiciary, and a free media have all been central to Hong Kong’s success,” he said. “I’ve no doubt that Hong Kong’s future success will depend on the rights and freedoms protected by that treaty.

“And I want to stress that Britain’s commitment to Hong Kong – enshrined in the Joint Declaration with China – is just as strong today as it was 20 years ago.”

Johnson added that it was essential “one country, two systems” continue to be the basis of Hong Kong’s way of life into the future.

In recent years, concerns have grown regarding the erosion of freedoms and the rule of law in Hong Kong. One episode in particular has given rise to anxiety: in late 2015, five owners and staff from a Hong Kong bookstore disappeared and were subsequently revealed to be in detention in China.

In their statements, the UK and US officials also called for democratic development to be pushed forward in Hong Kong. A political reform proposal, criticized by local pro-democracy groups as offering a sham version of universal suffrage – as Beijing would effectively retain the power to select Chief Executive candidates – was vetoed in the city’s Legislative Council in May 2016.

Saturday marks 20 years since Britain returned Hong Kong to China.

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