SIMIC

"We're seeing people start to question how long they can stay here. And whether being here is going to be effective for them long term," said Amcham president Tara Joseph.

"We've got lots of change in the terms of Hong Kong being at an inflection point politically," Ms Joseph said, referring to the new national security law China passed for Hong Kong and the overhaul to its electoral system last month.

Ms Joseph added these factors were further complicated by the China-US friction - in terms of trade and politics. "All of those items are at the top of the list for businesses here," she said.

While the current Joe Biden US presidential administration has vowed to use "all available tools" to counter China's unfair trade practices, it has yet to make clear its position on how it will handle tariffs with China that have hurt businesses in both countries, she told CNBC's "Street Signs Asia" .

"Let's take sanctions, for example, tit-for-tat between the US and China. Those add to risks of being here," she said. She said companies in Hong Kong are "rethinking, potentially also re-rating and measuring risk here now".

While Hong Kong has been able to contain the Covid crisis, Ms Joseph argued the city's restrictive travel and strict quarantine measures have caused businesses to re-evaluate their presence in the city.

"The Covid issue and the quarantines bring it down to a personal level," she said. Those living in Hong Kong have not been able to visit their families and "that starts to become a personal concern."

And that could hurt Hong Kong's reputation as a global financial hub.

"Hong Kong is also viewed as a place where you connect to travel, where you're able to have freedom of movement. And if we're not able to do that, it's going to affect the competitiveness of the city. So that is a growing