China's Xi set to begin Russia visit in show of support for Putin

Chinese President Xi Jinping is due to start a four-day visit to Russia on Wednesday, giving President Vladimir Putin an important diplomatic boost at a time when the Russian leader is keen to show his country is not isolated on the world stage.

Xi, whose country is locked in a tariff war with the United States, is expected to sign numerous agreements to deepen the already tight "no limits" strategic partnership with Moscow, which has consistently seen China crowned Russia's biggest trading partner.

China buys more Russian oil and gas than any other country and has thrown Moscow an economic lifeline that has helped it navigate Western sanctions imposed over its war in Ukraine.

Despite recent efforts under US President Donald Trump to reset US-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.

Xi wrote that China and Russia must "firmly maintain the post-war international order" in a signed article published by Russian media Wednesday.

"The two sides should jointly resist any attempt to disrupt and undermine China-Russia friendship and mutual trust," read the text of the article, Chinese state media reported. "China and Russia have always firmly supported each other on issues concerning each other's core interests and major concerns."

Russian Foreign Ministry spokeswoman Maria Zakharova called the visit "one of the central events in Russian-Chinese relations this year" in a news briefing this week.

Trump's special envoy Keith Kellogg said in February that Washington would try to disrupt Russia's close ties with countries like China. Days later, Xi and Putin reaffirmed their countries' "no limits partnership".

Both countries are aiming to show their "unbreakable bond" and demonstrate that the US "reverse Nixon" approach won't work, said Yun Sun, a China politics analyst at the Stimson Center in Washington.