After assuming office in March 2013, Chinese President Xi Jinping's first foreign visit was to Moscow on his way to the BRICS (Brazil–Russia–India–China–South Africa) summit in Durban, South Africa. In a speech to MGIMO, Russia's leading school of international relations, Xi enumerated the top priorities of Sino–Russian ties:

Exploitation of oil and gas resources; Military cooperation, including missile defense; and "Non-interference" in the "internal affairs" of other countries-code words for opposition to perceived U.S. global dominance, "meddling," and democracy promotion.[2]

This is a far cry from Sino–Russian relations for much of the Cold War, when the world's longest land border was marked by clashes and confrontation. After the Sino–Soviet split in 1960 ended the heyday of Sino–Soviet cooperation, Beijing and Moscow viewed each other with deep suspicion.

Fundamental differences between the two countries and their leaders escalated tensions. The Soviets and the Chinese disagreed on issues ranging from who would succeed Stalin as the leader of the Communist world to Soviet naval access to Chinese ports to Chinese demands for a more confrontational attitude toward the United States and an attendant willingness to risk nuclear war. Eventually, the two engaged in open warfare in 1969, with border clashes that began on Zhenbao Island/Damansky Island on the Ussuri River near Khabarovsk in the east and later spread to Xinjiang along the border with Kazakhstan.[3] Notably, these clashes are one of the few examples of two nuclear-armed powers engaging in active combat with each other. These tensions provided the opportunity for President Richard Nixon's opening to China and the establishment of Sino–American relations in 1972, as Beijing and Washington cooperated to balance against Moscow.

However, as the Cold War drew to a close, Sino–Soviet relations improved. At the May 1989 summit between Deng Xiaoping and Mikhail Gorbachev, the two nations set aside their border issues. At almost the same time, the Tiananmen Massacre in June 1989 and the subsequent Western imposition of sanctions on high-technology sales to China signaled the end of the strategic partnership between China and the United States in confronting the USSR.

As the Soviet Union collapsed, the power relationship between Moscow and Beijing steadily shifted in China's favor. Moscow was preoccupied with withdrawal from Eastern Europe, a difficult divorce from the former Soviet republics, and managing the chaotic process of economic privatization. Meanwhile, the Chinese economy steadily grew, as Deng Xiaoping's policies of economic reform and opening to the outside world progressed, especially after Deng's "southern tour" in 1992. Boris Yeltsin and Jiang Zemin both pushed to realign the two states on the basis of pragmatism, rather than Communist solidarity. They were assisted by such figures as Yevgeniy Primakov, Russia's staunchly anti-American foreign minister (1996–1998) and Prime Minister (1998–1999), and China's Qian Qichen, vice premier (1993–2003) and the last Chinese foreign minister (1988–1998) who was a member of the Chinese Communist Party Politburo.[4]

While neither Russia nor the PRC actively sought confrontation with the United States during the 1990s, both tried to facilitate emergence of a multipolar international environment that would constrain American power. This was evidenced in 1997, when Chinese Premier Li Peng returned from a trip to Moscow proclaiming a "strategic partnership" with Russia to "offset the influence of the United States." Later that year, China and Russia issued a joint declaration on the "multipolar world," calling for a new international order, reflecting Chinese concerns over the strengthening U.S.–Japanese alliance and Taiwan's independence movement and Russia's concerns over NATO enlargement and Chechen separatism.[5]

An essential element of this realignment centered on border demarcation and demilitarization, involving not only Russia and China, but the various Central Asian republics that had gained their independence when the USSR disintegrated. China and Russia both view Central Asia as a focus of competition between the two states and see the region as tied to their internal security concerns.[6] China is concerned about potential support for Uighur organizations in Xinjiang, and Russia is concerned about potential support for spreading Islamist radicalism and terrorism inside Russia.