Chinese leader Xi Jinping's top foreign policy adviser Wang Yi is set to arrive in Moscow this week, coinciding with US President Joe Biden's visit to Ukraine. This trip comes at a time of strained relations between the US and China, and the timing of the two trips underscores the sharpening of geopolitical fault lines between the world's two superpowers. Wang Yi's visit is seen as an attempt by China to balance its diplomatic relations with both the US and Russia.