Sen. Patrick Toomey told CNBC on Thursday that the U.S. must respond to Beijing's latest encroachment on the autonomy of Hong Kong, which comes in the form of a new national security law approved by China's parliament.
The Pennsylvania Republican touted legislation that he's proposed, along with Sen. Chris Van Hollen, D-Md., saying the bill would be in addition to any action resulting from recent State Department moves.
"The idea of this bill is to send a very clear message to Beijing that we're not going to sit by idly while they systemically destroy the autonomy that they promised to Hong Kong," Toomey said on "Squawk Box."
The prospect of the Chinese-imposed national security law, announced last week, has triggered another wave of protests in the former British colony, following the widespread pro-democracy demonstrations there last year.
Hong Kong, a special administrative region of China, has been ruled under a "one country, two systems" principle, giving the city's residents some freedoms that those on the mainland do not have. In the 1997 handover, China promised to keep those freedoms in place for 50 years.
Critics of the national security law believe it would further erode those freedoms.
Secretary of State Mike Pompeo on Wednesday said the U.S. no longer considered Hong Kong autonomous from China, a decision that carries broad economic implications.
Pompeo's decision unfortunately recognizes the "obvious," Toomey said, arguing Hong Kong does not have the autonomy "that was the precondition for a different relationship between the United States and Hong Kong versus, say, every other city in China."
For example, Toomey said tariffs imposed on mainland China, but not Hong Kong, could lose that distinction as a result of Pompeo's determination.
If his bill, the Hong Kong Autonomy Act, were to become law, Toomey said the State Department would have to list entities and people in China who "are responsible for inflicting this crackdown on Hong Kong."
"They will be subject to sanctions themselves, financial sanctions including things like freezing their assets but also secondary sanctions, which is to say restricting the activities of banks that finance those individuals and those entities," Toomey said. "I think that's a pretty big hammer to be wielding."
Toomey, a member of the Senate Finance and Budget committees, said he believes China's new national security law is "much worse" than the extradition proposal last year that triggered the widespread demonstrations.
"This would simply impose the entire Chinese criminal justice, or criminal injustice system, directly on the people of Hong Kong," he said. "It's pretty essential, I think, that we respond to that."