Wang said the world’s second largest economy also “deplores the outbreak of conflict between Ukraine and Russia,” according to a statement posted on the Ministry of Foreign Affairs website. The remarks were published after a call between Wang and Ukrainian Foreign Minister Dmytro Kuleba, the most senior exchange since Russia’s Vladimir Putin launched the invasion Thursday.

Wang also acknowledged the conflict was a “war,” rather than a “special military operation” as described by Russia. Kuleba said Ukraine was willing to strengthen communication with China and that it looked forward to China’s “mediation for the realization of the ceasefire,” according to the statement.

“This is a very important event and signals the very high attention that the Chinese government is paying to the Ukraine crisis,” said Henry Wang Huiyao, founder of the Center for China & Globalization policy research group in Beijing. “If both Ukraine and Russia invite China to be a mediator, then China would probably join.”

The war is testing Chinese President Xi Jinping’s commitment last month to a “no limits” relationship with Putin, as the U.S. and its allies pile on sanctions and press Beijing to take as stand against military aggression. In recent days, Xi has urged Putin to pursue negotiations and China’s United Nations ambassador abstained from, rather than opposing, a Security Council resolution condemning the attack. 

The call between Wang Yi and Kuleba came as convoys of Russian military vehicles bore down on the Ukrainian capital of Kyiv and other major cities, prompting warnings that Moscow could unleash a mass bombardment on population centers. 

Still, China has refrained from publicly calling for a ceasefire or describing the war as an “invasion,” and thus a violation of the UN-guaranteed sovereignty Beijing frequently vows to uphold. China hasn’t criticized Russia, and continues to voice support its security concerns and blame the U.S. for precipitating the crisis. 

China boasts deep economic ties with Ukraine, and Wang Yi expressed concern over the safety of Chinese citizens there, estimated at 6,000 when the invasion began. Beijing’s support is seen as essential to Moscow’s efforts to weather international sanctions, which are cutting if off from huge swaths of the world’s trade, finance and travel. 

Some 2,500 Chinese nationals have been relocated from Ukraine as of midday Wednesday, Foreign Ministry spokesman Wang Wenbin said at a regular press briefing in Beijing. He sidestepped a question on whether Xi would speak with Ukrainian President Volodymyr Zelenskiy, saying only that Beijing’s communication links with Kyiv were open.

During the call, Wang Yi said China always upholds respect for sovereignty and territorial integrity of all countries, and called on Ukraine and Russia to “find a solution to the issue through negotiations,” according to the statement. China supports all constructive international effort conducive to “political settlement,” he added.

“As the war continues to expand, the top priority is to ease the situation to prevent the conflict from escalating or even getting out of control, especially to prevent harm to civilians, and to ensure the safe and timely access of humanitarian aid,” the Chinese foreign minister said.