A US global security report says China is "working to meet its goal of fielding a military by 2027 designed to deter US intervention" in a potential crisis involving Taiwan.

The Office of the Director of National Intelligence released the annual report on worldwide threats on Wednesday.

The report says that as President Xi Jinping begins his third term as China's leader, Beijing will continue to apply pressure on Taiwan to move toward unification.

It says China will also take stronger measures to push back against perceived increases in US support to Taiwan. It says Beijing "could include more Taiwan Strait centerline crossings or missile overflights of Taiwan."

The report also says that to counter the US, "China will maintain diplomatic, defense, economic, and technology cooperation with Russia."

At a Senate hearing on Wednesday, Director of National Intelligence Avril Haines noted that China has continued to "deepen" its relationship with Russia.

She said the US government sees China "providing assistance to Russia in the context of the conflict." She noted that the degree of the assistance is "a very real concern."