Xi Jinping hailed his landmark visit to Moscow Monday as giving "new momentum" to Chinese-Russian ties ahead of talks with Vladimir Putin on Beijing's proposals to stop the fighting in Ukraine.
The summit between the Russian president and the Chinese leader comes as China seeks to portray itself as a neutral party in the Ukraine conflict.
Washington has accused Beijing of mulling arms exports to Moscow -- claims China has vociferously denied.
Xi's three-day trip also serves as a show of support for internationally isolated Putin, just days after a war crimes tribunal issued a warrant for his arrest over accusation of unlawfully deporting Ukrainian children.
Landing at Moscow's Vnukovo Airport, Xi was greeted by Deputy Prime Minister Dmitry Chernyshenko on a red carpet as a military brass band played the countries' anthems, Russian state media showed.
"I am confident the visit will be fruitful and give new momentum to the healthy and stable development of Chinese-Russian relations," Xi was quoted by Russian news agencies as saying shortly after landing.
"In a world of volatility and transformation, China will continue to work with Russia to safeguard the international system with the UN at its core," he said.
Xi described China and Russia as "good neighbours" and "reliable partners" and said the two would work together to defend "true multilateralism".
The two leaders are due to discuss China's 12-point position paper on the Ukraine conflict, which includes a call for dialogue and respect for all countries' territorial sovereignty.
"One way or another, issues raised in (Beijing's) plan for Ukraine will be touched upon during the negotiations. Comprehensive explanations will be given by President Putin" of the Russian position, Kremlin spokesman Dmitry Peskov told reporters.
Putin and Xi are set to have an "informal" one-on-one meeting and dinner later Monday before talks on Tuesday, Putin's top foreign policy adviser Yuri Ushakov told Russian news agencies.
Putin has welcomed Beijing's statements on Ukraine as being indicative of a willingness to play a "constructive role" in ending the conflict.
But Kyiv on Monday reiterated calls for Russia to withdraw its forces from Ukraine ahead of Xi's arrival.
"The formula for the successful implementation of China's 'Peace Plan'. The first and foremost point is the surrender or withdrawal of Russian occupation forces from (Ukrainian territory) in accordance with international law and the UN Charter," the secretary of Ukraine's National Security and Defence Council, Oleksiy Danilov, wrote on Twitter.
A day before Xi's arrival, a defiant Putin went to the Russian-held Ukrainian city of Mariupol -- his first visit to territory captured from Kyiv since Moscow's forces pushed across the border in February 2022.
Xi's visit also comes just days after the International Criminal Court (ICC) issued an arrest warrant for Putin on the accusation of unlawfully deporting Ukrainian children.
Beijing said on Monday the ICC should avoid what it called "politicisation and double standards" and respect the principle of immunity for heads of state.
The court should "uphold an objective and impartial stance" and "respect the immunity of heads of state from jurisdiction under international law", foreign ministry spokesperson Wang Wenbin told a regular briefing.
The solution to the Ukraine conflict, he added, remained "dialogue and negotiation".
Beijing and Moscow have drawn closer in recent years under a partnership that has served as a diplomatic bulwark against the West.
China has lambasted what it sees as a US-led campaign of pressure against Russia as Moscow's campaign in Ukraine drags on, instead calling for what it calls "impartial" mediation of the conflict.
"No single country should dictate the international order," Xi wrote in a Russian newspaper article published on Monday.
"China has all along upheld an objective and impartial position based on the merits of the issue, and actively promoted peace talks," he added.
Beijing's stance has drawn criticism from Western nations, which say China is providing diplomatic cover for Moscow's armed intervention.
They argue that China's proposals are heavy on grand principles but light on practical solutions.
The United States last week said China's proposals would simply consolidate "Russian conquest" and allow the Kremlin to prepare a fresh offensive.
"We don't support calls for a ceasefire right now," National Security Council spokesman John Kirby said Friday.
"We certainly don't support calls for a ceasefire that would be called for by the PRC in a meeting in Moscow that would simply benefit Russia," he said, referring to the People's Republic of China, the country's official name.
Analysts say Xi's moves are unlikely to yield a cessation of hostilities, but his trip will be closely watched in Western capitals.
The Wall Street Journal has reported that Xi could also be planning his first call with Ukrainian President Volodymyr Zelensky since the conflict began.
Zelensky has said he would welcome talks with his Chinese counterpart.