The U.S. will sanction at least a dozen China officials over the disqualification of four pro-democracy Hong Kong politicians, news reports said Monday citing sources within the Trump administration.

Last month, the National People's Congress in Beijing passed a resolution requiring the "patriotism" of all legislators - leading to the swift dismissal of four elected members of Hong Kong's legislative assembly and the subsequent resignation of another 15 in protest.

American retaliatory measures will likely include freezing assets and imposing further financial sanctions on up to 14 mainland and Hong Kong officials who implemented the NPC's decision - including members of the congress - people familiar with the matter told Reuters.

This will be the third round of American economic sanctions on China's Communist Party officials and Hong Kong government members this year - and given president-elect Joe Biden's promise to crack down on China's human rights violations more are on the horizon.

When in power, Biden will "fully enforce" the Hong Kong Human Rights and Democracy Act "including sanctions on officials, financial institutions, companies and individuals," senior advisor Tony Blinken said in May.

The president-elect took a firm stance against China's encroaching dominance over Hong Kong in the early days of his campaign.

"The United States does need to get tough with China," he wrote in a January opinion article for Foreign Affairs magazine - referencing Hong Kong's desire for "honest governance" and promising an annual international "summit for democracy" if elected.

While Hong Kong is a China-controlled territory, the city was guaranteed a measure of autonomy in the 1984 Sino-British Joint Declaration. This agreement has been breached often in the past year alone, according to UK Foreign Secretary Dominic Raab.

"China has failed to live up to its international obligations with respect to Hong Kong," Raab wrote in his bi-annual report on the state of Britain's former colonial protectorate.

Taking a page from their American counterparts, Hong Kong police froze the bank accounts of opposition lawmaker Ted Hui on Monday. The legislator announced he and his family had fled last week to Denmark where they will seek asylum.