The US added two Chinese companies to its blacklist, claiming they threaten national security, according a statement Thursday by the Commerce Department.

The Chinese National Overseas Oil Corporation (CNOOC) was added to the US' economic list and Skyrizon was added to the military end-user list.

"Both companies threaten US national security, CNOOC by helping China intimidate neighbors in the South China Sea and Skyrizon for its capability to develop, produce, or maintain military items, such as military aircraft engines," the statement said.

Commerce Secretary Wilbur Ross said Beijing's actions to acquire intellectual property and technology for its militarization efforts are a threat to the US' national security and the security of the international community.

Intellectual property and technology transfer have been significant but unresolved issues between Washington and Beijing that have engaged in a trade conflict during President Donald Trump’s administration.

Before he leaves office Jan. 20, Trump has intensified pressure on Chinese companies, including TikTok and WeChat apps, and has tried to delist several that traded on the New York Stock Exchange. /aa