A senior US government official says China is "taking a very careful approach" to Russia's invasion of Ukraine.
White House National Security Advisor Jake Sullivan spoke at an event hosted by a US think tank on Thursday.
Sullivan said the United States has not seen any form of direct military assistance by China to Russian forces in Ukraine. He added that Washington has also not seen Beijing undertake systematic efforts to help Moscow evade sanctions and export controls.
Sullivan said the US believes China has not taken steps that cross lines in relation to those issues where it was pressed particularly hard by the White House.
But he pointed out that China showed a pro-Russia stance on occasions such as votes at the United Nations on resolutions condemning the invasion.
Sullivan was asked whether the US would defend Taiwan if China invades. He said the US approach is "about ensuring that the day never comes where the question is called as to whether or not we have to defend Taiwan because we will have effectively deterred it."
Sullivan stressed that the US stance on Taiwan remains the same, including the one-China policy.