President Xi Jinping welcomed his Russian counterpart Vladimir Putin as an "old friend" as the two began a series of meetings in Beijing on Tuesday at a time when their countries face both overlapping and differing challenges from the United States.

"China-Russia relations have withstood the test of international changes," Xi told Putin.

The president added that Beijing is willing to work with Moscow to "promote the construction of a more just and reasonable global governance system".

On Monday, Xi proposed the Global Governance Initiative at the Shanghai Cooperation Organization (SCO) summit in Tianjin, which highlights principles such as international rule of law and multilateralism.

Putin, for his part, addressed Xi as "dear friend" and said that Moscow’s ties with Beijing are "at an unprecedentedly high level".

"Our close communication reflects the strategic nature of Russian-Chinese ties, which are currently at an unprecedented level," he said.

In a nod to cooperation between the two countries during the Second World War, Putin said "we were always together then, and we remain together now."

Following their formal talks, they planned to have another meeting over tea with some of their top aides.

The talks come the day after Xi and Putin attended the SCO summit and the day before a grand Chinese military parade in Beijing to mark the 80th anniversary of the victory in the Chinese People's War of Resistance Against Japanese Aggression and the World Anti-Fascist War.

The two leaders also held a three-way meeting with Mongolian President Ukhnaa Khurelsukh ahead of their talks.

Xi said the three countries should strengthen solidarity and cooperation and increase mutual support. (Agencies)