Beijing's top representative in Hong Kong denounced a Hong Kong-related bill passed by the United States House of Representatives on Wednesday, saying it is a gross interference in China's internal affairs in the name of human rights and democracy.

The Hong Kong Human Rights and Democracy Act of 2019 would take effect if approved by US Senate and the president after deliberations in Congress. The bill requires the US government to assess Hong Kong's autonomy each year to determine whether to revoke the city's separate customs status in trade and finance.

The spokesman for the Liaison Office of the Central People's Government in the Hong Kong Special Administrative Region warned the US side not to manipulate Hong Kong issues from behind the scenes, adding that any attempt to mess up Hong Kong and China is bound to fail.

The spokesman said the bill would embolden radicals who have committed arson, smashed shops and attacked police officers, as the US congress and some politicians turned a blind eye to violence and crimes.

Calling out these politicians' hypocrisy and double standards on Hong Kong affairs, the spokesman questioned how the US government and their police would react to these riotous behaviors if it happened in the US.

The spokesman reiterated that the city's practice of "one country, two systems" has proved a notable success, which is also in the interest of the US as a large number of US companies are running their businesses in Hong Kong.

Different sectors in Hong Kong also voiced strong opposition against the United States over the bill.

Hong Kong deputy to the National People's Congress Henry Cai Yi said it is widely acknowledged that Hong Kong has made solid progress in terms of democracy, freedom and rule of law since its return to the motherland in 1997.

Brave Chan Yung, also deputy to the NPC, said the House of Representatives, elected by Americans, does not have a say in the affairs of Hong Kong people.

NPC deputy Maggie Chan Man-ki slammed the US's intention to contain China's peaceful development by disrupting the peace and order in Hong Kong, urging the city's people not to fall into the trap of the US.

The bill is a political tactic that will give the US more bargaining chips during trade talks between China and the US, Starry Lee Wai-king, chairman of the Democratic Alliance for the Betterment and Progress of Hong Kong, the city's largest political party, pointed out.

"I urge the US to stop interfering in the special administration region's affairs," Lee said.

Lawrence Ma Yan-kwok, chairman of the Hong Kong Legal Exchange Foundation, noted that the act, from the perspective of international law, will contravene a United Nations' General Assembly resolution.

According to resolution 2131, no state has the right to intervene, directly or indirectly, for any reason whatever, in the internal or external affairs of any state. All forms of interference or attempted threats against the personality of the state or against its political, economic and cultural elements are condemned.

The barrister said the bill is devised to intervene in the affairs of Hong Kong, which are China's internal affairs.

Ma predicted the bill might have a political effect of encouraging rioters in Hong Kong.

By doing so, the US is trying to use Hong Kong as a "bargaining chip" in the US-China trade tension, Ma added.

The passage of the act by the US House of Representatives is a "substantive support" for the opposition camp in Hong Kong and will greatly embolden them to resort to tougher and more extreme acts, said Ronny Tong Ka-wah, Executive Councilor and barrister.

Several lawmakers of the pro-establishment camp also expressed regret at the passing of the bill and voiced opposition over the act.

Martin Liao Cheung-kong, the convener of the pro-establishment camp, said the act will impose great threats on Hong Kong's business environment and economic and trade relations between the city and the US, adding it will also jeopardize the US-China relationship.

"Thus US interests are bound to be adversely affected as the result," Liao noted.

Liao, also a barrister, slammed the US Congress for listening to one-sided testimonies, saying such acts are "biased" and "unjust".