Chinese President Xi Jinping and Russian President Vladimir Putin are expected to meet in person on Friday during the opening ceremony of the Winter Olympics in Beijing.
Putin's first in-person meeting with President Xi in two years comes as Chinese and Russian relations with Europe and the United States continue to deteriorate.
Russia continues to maintain around 100,000 troops along its border with Ukraine. The United States and NATO have said there is a real threat Russia could invade Ukraine.
China's time in the global spotlight as host of the 2022 Winter Games is being overshadowed by diplomatic boycotts from several Western countries over Beijing's human rights record, and geopolitical tension over Taiwan and the South China Sea.
"Putin's visit to China during the Olympics not only has strong symbolic significance to send a message of unity and firm ties between the two heads of state, but also serves to increase global diplomatic weight and improve China's international image in the face of increasing boycotts by Western countries," Velina Tchakarova, head of the Austrian Institute for European and Security Policy (AIES) in Vienna, told DW.
On Thursday, China's official Xinhua news agency published a signed letter from Putin praising Russia and China's "centuries-old traditions of friendship and trust."
Putin wrote that Russia and China's "strategic partnership of coordination" has entered a "new era," reaching an "unprecedented level" and becoming a "model of efficiency, responsibility, and aspiration for the future."
The Russian president then lists several big plans for the future of Sino-Russian ties, including developing economic and energy partnerships.
Beijing's position on Ukraine tensions
Putin's letter did not specifically mention strategic issues, and China traditionally maintains a position of neutrality when commenting on tensions outside its sphere of influence.
In a phone call last week with US Secretary of State Antony Blinken about the ongoing threat of conflict in Ukraine, Chinese Foreign Minister Wang Yi spelled out Beijing's position, calling on all parties to "stay calm" and refrain from doing anything to "agitate tensions and hype up the crisis."
However, Wang also said that Russia's security concerns "should be taken seriously."
"It seems that in such a tense confrontation China has picked the Russian side, and did it openly, which deviates from its traditionally more neutral approach to sensitive issues," said Danil Bochkov, a fellow at the Russian International Affairs Council in Moscow.
"It might be a signal of a more trustworthy relationship from both states resembling a quasi-allied structure," he told DW.
Some signs of this include China and Russia discussing ways to jointly develop alternative international payment systems in the face of potential western sanctions.
Even if sidestepping US-dollar-dominated transactions is easier said than done, Russia and China want to show the world they are ready to work together.
"We are consistently expanding settlements in national currencies and creating mechanisms to offset the negative impact of unilateral sanctions," Putin wrote in his letter.
"They are signaling that they are unhappy with the current international order and that they will work together to reshape it," said Theresa Fallon, director of the Centre for Russia Europe Asia Studies, a think tank in Brussels, told DW.
"Russia needs a powerful ally because of its isolation from the West, while China needs a reliable international partner with regional power projection to bolster its global influence and global geopolitical clout," said Tchakarova from the AIES.
Putin said in his pre-summit letter that Russia and China, "play an important stabilizing role in today's challenging international environment."
He added that the two countries, while under international pressure for flouting democratic norms, do "promote greater democracy in the system of international relations to make it more equitable and inclusive."
Despite Foreign Minister Wang's remarks indicating China's tacit support of Russia's security interests, Beijing would likely prefer stability in Eastern Europe.
China has many trade links with Ukraine via the Belt and Road Initiative, along with investments in Eastern Europe, which could be strained by overt conflict.
"I don't think China ignores the fact that if there is a crisis in Ukraine, it's going to have bigger consequences, and it’s not necessarily in Beijing’s interest to see that happen," said Zsuzsa Anna Ferenczy, a postdoctoral researcher and a former political advisor in the European Parliament.
And Shi Yinhong, a professor of international relations at Renmin University in China, told DW there is no indication that China would violate its doctrine of neutrality and openly support a Russian invasion of Ukraine.
"China will not publicly oppose in any way Russia's probable invasion of Ukraine, however, they will not support it either," he said. "While China will oppose any Western sanctions against Russia, it will not do anything for Russia directly to counter sanctions," he added.
As far as a Russian invasion of Ukraine during the Beijing Winter Olympics, experts say one of the most important things for Xi during his talks with Putin will be to ensure that the Games are not overshadowed by an armed conflict in Europe.
"He wants reassurance that the crisis in Ukraine won’t become an obstacle for the Winter Olympics," said Ferenczy.
Indeed, Putin said in his letter that Olympic diplomatic boycotts were an "attempt by a number of countries to politicize sports for their selfish interests."
Chinese expert Shi said Putin is unlikely to launch a military invasion at a time when the Winter Olympics is about to begin in China.
"I don't think Putin would launch an invasion of Ukraine during the Beijing Winter Olympics, as it could embarrass China greatly," he said.
Edited by: Wesley Rahn