Steven Roach on Russia-China relations against the backdrop of the war in Ukraine

“The best thing China can do now is to mediate a peace deal between Russia and Ukraine,” says economist Steven Roach.

“I think that only one person in the world has leverage over Vladimir Putin and that is [Chinese President] Xi Jinping,” Roach told Squawk Box Asia on CNBC.

“I mean, China really holds the trump card here, and I think Xi should take advantage of this moment,” he added.

Fighting intensified in many cities of Ukraine, and Putin was not going to give up.

The US, UK and European Union have tried to impose sanctions on Russia after its invasion of Ukraine. However, China said it would not participate in the sanctions and refused to call Russia’s attack on Ukraine an invasion.

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China also abstained from voting on a UN resolution condemning Russia for invading Ukraine.

Instead, Beijing pushed ahead with the talks and positioned itself further away from Russia than was shown during Xi’s high-profile meeting with Putin in early February. During this meeting on the opening day of the Beijing Winter Olympics, the leaders announced a “borderless” partnership, promising to cooperate more against the West.

Roach said China should instead “threaten to tear the rug” if Putin “doesn’t play ball.” He said it would be a mistake for Beijing to double down on partnership with Moscow when the world is putting extreme pressure on Russia. Roach said that would brand China as the culprit for “a long, long time.”

“He can’t afford to stick to this course – that would be a mistake of historic proportions for Xi Jinping,” Roach said.

— Evelyn Cheng of CNBC contributed to this report.