NEIGHBORLY TIES: Chinese Premier Zhou Enlai signs the Sino-Soviet Treaty of Friendship, Alliance and Mutual Assistance in the Kremlin, Moscow, on February 14, 1950 (FILE)

HEARTFELT APPLAUSE: Nikolai Roshchin, the first Soviet Ambassador to China, watches the celebration of the second anniversary of the founding of the People's Republic of China in Beijing's Tiananmen Square on October 1, 1951 (XINHUA )

YOUTHFUL FRIENDSHIPS: A Chinese youth delegation takes a group photo with their Soviet counterparts in Moscow's Red Square in 1951 (FILE)

PREMIER IN MOSCOW: Chinese Premier Zhou Enlai makes a speech upon his arrival in Moscow for a visit on August 17, 1952 (FILE)

ADVANCED ASSISTANCE: Representatives of the Chinese and Soviet governments sign a protocol on jointly conducting scientific and technological research in Moscow on January 18, 1958 (XINHUA)