Ukrainian drones targeted Moscow for a third day on Wednesday, forcing most of the Russian capital's airports to close hours before Chinese President Xi Jinping was due to fly in for a pomp-filled visit that Kyiv has made clear it opposes.

The Trump administration has said it wants to pull apart Russia and China, but the two countries need each other too much.

Despite recent efforts under U.S. President Donald Trump to reset U.S.-Russia ties, Putin is expected to present a united front with Xi against Washington, whose dominance and "exceptionalism" both countries have questioned, arguing for a more multipolar world instead.