“This will surely increase the doubt, anxiety, and uncertainty of foreign businesses in Hong Kong.”

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It comes amid a Beijing crackdown on purported spies that has already affected advisory and due diligence firms carrying out work in China.

Several large US consulting firms in the country were raided last year, while in January, Beijing accused British intelligence service MI6 of recruiting and training a spy in a consulting agency to gather intelligence in China.

Many multinational companies have already moved their Asian headquarters away from Hong Kong to locations such as Singapore due to concerns about tightening Chinese control.

Under the new laws, citizens could also be imprisoned for keeping old copies of Apple Daily, the pro-democracy newspaper shut down in 2021. Its founder, Jimmy Lai, is on trial for a range of charges under the national security laws.

Human Rights Watch acting China director Maya Wang said: “The new security law will usher Hong Kong into a new era of authoritarianism.

“Now even possessing a book critical of the Chinese government can violate national security and mean years in prison in Hong Kong.”

The imposition of Article 23, which was rushed through Hong Kong’s pro-Beijing Legislative Council in less than a fortnight, is highly symbolic for citizens of the city.

It fulfils a constitutional obligation for Hong Kong to enact its own security legislation after British rule ended. But previous attempts to do so in 2003 were shelved amid widespread public protests.

Authorities say the new laws close loopholes in the national security regime, even though existing laws have already been used to jail pro-democracy protesters who challenged China’s rule over the semi-autonomous territory.

Hong Kong chief executive John Lee branded the changes a “historic moment”.

British Foreign Secretary David Cameron said: “The overall impact of Hong Kong’s new national security law is that it will further damage the rights and freedoms enjoyed in the city.

“It undermines Hong Kong’s implementation of binding international obligations, including the Sino-British Joint Declaration and the International Covenant on Civil and Political Rights.”

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Sir Iain Duncan Smith, a former Conservative Party leader, said: “This change to the existing law in Hong Kong is even worse and more oppressive. This will put Hong Kong’s status as an English Common Law jurisdiction in very serious question.”

The Telegraph, London

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