The military claimed in a strategy document released on Thursday that Russia poses "acute threats" while China is the "most consequential" threat to the US.

China "presents the most consequential and systemic challenge, while Russia poses acute threats -- both to vital US national interests abroad and 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.

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It underlines Chinese "rhetoric on Taiwan's self-rule," which Beijing has threatened to seize by force if necessary, as a "potentially dangerous factor that raises the possibility of error and jeopardizes regional peace."

The strategy wrote that 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." 

To confront the threats posed by China and Russia, it underlined the importance of working with allies and other partners, stating that such cooperation is "foundational for US national security interests."

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This comes after the UK government said in a statement yesterday that new Prime Minister Rishi Sunak expressed optimism that he would soon meet with Ukrainian President Volodymyr Zelensky.

Earlier, Zelensky stated that he spoke with Sunak over the phone and encouraged him to visit Ukraine at a time when the UK PM had announced that Zelensky and the Ukrainian people can depend on London's support.

According to the UK government, "President Zelensky congratulated the Prime Minister on his appointment and wished him a happy Diwali. The Prime Minister thanked him and said he hoped they would see each other in person soon."

Moreover, US President Joe Biden spoke with Sunak in their first phone call, according to a White House readout.

"President Joseph R. Biden, Jr. spoke today with Prime Minister Rishi Sunak of the United Kingdom to congratulate him on his appointment," Tuesday's release read, noting that the "leaders agreed on the importance of working together to support Ukraine and hold Russia accountable for its aggression, address the challenges posed by China, and secure sustainable and affordable energy resources."