China has summoned the US ambassador to demand that the United States scrap legislation backing Hong Kong's pro-democracy movement, or "bear all the consequences", the foreign ministry said Tuesday.
The Hong Kong bill awaiting President Donald Trump's signature supports human rights and democracy in the city, while threatening to revoke the territory's special economic status.
A separate measure bans the sale of tear gas, rubber bullets and other equipment used by the security forces to suppress pro-democracy protests.
Vice foreign minister Zheng Zeguang summoned US ambassador Terry Branstad on Monday to voice a "strong protest" over the bill, the ministry said in a statement.
The legislation "brazenly interferes in China's internal affairs" and "indulges and supports the violent criminal behaviour by 'anti-China disrupting Hong Kong' forces," the ministry said.
Trump has not indicated whether he will sign the legislation into law, saying last week that while he stood with Hong Kong, he also stood with his "friend", President Xi Jinping.
The foreign ministry urged the US to "immediately correct its mistakes, prevent the above-mentioned Hong Kong-related bill from becoming law, and stop any words and deeds that interfere in Hong Kong affairs and China's internal affairs."
"Otherwise, the US side must bear all the consequences," it said.
A US embassy spokesman told AFP that Branstad told Zheng that the United States was watching the situation in Hong Kong "with grave concern".
"He conveyed that we condemn all forms of violence and intimidation," the spokesman said.
"The ambassador added that the United States believes that societies are best served when diverse political views can be represented in genuinely free and fair elections."