China "presents the most consequential and systemic challenge, while Russia poses acute threats -- both to vital US national interests abroad and to the homeland," the unclassified version of the National Defense Strategy said.

"The most comprehensive and serious challenge to US national security is (China's) coercive and increasingly aggressive endeavor to refashion the Indo-Pacific region and the international system to suit its interests and authoritarian preferences," the strategy said.

It highlights Chinese rhetoric over self-ruled Taiwan -- which Beijing has vowed to take control of, by force if necessary -- as a destabilizing factor that risks miscalculation and threatens peace in the area.

The threat posed by Moscow has been "demonstrated most recently by Russia's unprovoked further invasion of Ukraine. The Department (of Defense) will support robust deterrence of Russian aggression against vital US national interests, including our treaty Allies," the strategy said.

It emphasized the need for collaboration with allied countries and other partners to counter the dangers posed by China and Russia, saying such cooperation is "foundational for US national security interests."