Hong Kong on Saturday hit back at the United States over its latest sanctions on six pro-China officials, slamming the move as "insane, shameless and despicable".

The US announced on Friday it was imposing sanctions on the half dozen officials, including Hong Kong's sole representative to China's top lawmaking body, over the arrests of more than 50 pro-democracy activists in the financial hub.

In a statement, the Hong Kong government expressed "utmost anger" and denounced the "coercive measures" which it said was Washington's latest attempt to intervene in China's internal affairs and obstruct the city's effort to safeguard national security.

China last year imposed a draconian security law in Hong Kong after widespread and sometimes violent protests that sought to preserve the territory's separate freedoms.

At least 90 people have been arrested under the security law which mandates up to life imprisonment for any offence Beijing views as "secession, subversion, collusion with foreign forces and terrorism".

At least 90 people have been arrested under the security law
At least 90 people have been arrested under the security law AFP / Anthony WALLACE

The latest mass arrest, described by US Secretary of State Mike Pompeo as "appalling", include US-born human rights lawyer John Clancey, prominent activist Joshua Wong and law professor Benny Tai.

"The US Government has exploited every incident and excuse to make slandering remarks about the National Security Law," a government spokesperson said in a statement.

"We could not help but suspect that the National Security Law has touched a nerve of those foreign or external forces," the spokesperson added.

The US has earlier imposed sanctions on Hong Kong's top leader, Chief Executive Carrie Lam, who later acknowledged that she has had to rely on cash and can no longer hold a bank account.

Yesterday's sanctions hit Tam Yiu-Chung, the Hong Kong delegate to the National People's Congress Standing Committee, and You Quan, the vice chairman of the Chinese government group that handles policy toward Hong Kong and fellow former colony Macau.

Three Hong Kong security officials were also hit by the sanctions, which restrict any US transactions with them.

China