Chinese leaders are increasingly concerned about a fledgling independence or secessionist movement in the former British colony of Hong Kong, which returned to mainland rule in 1997 amid promises of wide-ranging autonomies including judicial independence under a "one country, two systems" arrangement.
China's parliament last year staged a rare interpretation of the Basic Law, as Hong Kong's mini-constitution is called, and staged one of Beijing's most direct interventions into the city's legal and political system since the 1997 handover.
"The interpretation fully demonstrates the Chinese central leadership's resolve in upholding the 'one country, two systems' principle and its firm stand against any attempt at secession of Hong Kong from the Chinese nation," parliament chief Zhang Dejiang said in his annual report to parliament.
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The National People's Congress had ruled last November that all lawmakers must swear allegiance to Hong Kong as part of China and that candidates would be disqualified if they changed the wording of their oath of office or if they failed to take it in a sincere and solemn manner.
Two lawmakers, Yau Wai-ching and Baggio Leung, who pledged allegiance to a "Hong Kong nation" during their oath-taking, have since been barred from office after being democratically elected. Four other pro-democracy lawmakers face possible disqualification for improper oath-taking amid ongoing legal proceedings.
"It embodies the firm will of the 1.3 billion Chinese people, including those in the Hong Kong region, to safeguard their country's sovereignty, security and developmental interests," added Zhang, who is also the ruling Communist Party's third-ranked leader.
Hong Kong is an inseparable part of China and any attempt at Hong Kong independence is a violation of "one country, two systems", China's constitution and Hong Kong's Basic Law, he said.
A former Hong Kong secretary for justice, Elsie Leung, said it was important for Hong Kong's prosperity and integrity that the central government made a statement on independence.
"This is the bottom line [of China] and cannot be over written," Leung, now a vice-chairperson of a parliamentary committee on the Basic Law, told reporters in Beijing before the release of Zhang's report.
While Communist Party rulers in Beijing have ultimate control over Hong Kong, their perceived growing interference in the financial hub's affairs has stoked tensions and protests including the "Occupy" civil disobedience movement in 2014 that saw major roads blocked for nearly three months in a push for full democracy.
Premier Li Keqiang also warned over the weekend in his annual work report to parliament that the notion of Hong Kong independence would lead nowhere.
A Hong Kong member of China's top advisory body now in Beijing said a person close to Xi Jinping had once told him the Chinese leader had described Hong Kong as "very troublesome" for China.
With Hong Kong due to select a new leader in an election on March 26, the delegate, who declined to be named, said it was likely Xi wanted someone who could better manage the city and not bring an even bigger headache for Beijing.
