Xi Jinping, poised to clinch a third five-year term as China's leader, will on Sunday preside over the most dramatic moment of the Communist Party's twice-a-decade congress and reveal the members of its elite Politburo Standing Committee.

Xi's break with precedent to rule beyond a decade was set in motion when he abandoned presidential term limits in 2018. His norm-busting as China's most powerful ruler since Mao Zedong has made it even harder to predict who will join him on the standing committee.

The 69-year-old leader's grip on power appears undiminished by a sharp economic slowdown, frustration over his "COVID zero" policy, and China's increasing estrangement from the West, exacerbated by his support for Russia's Vladimir Putin.