The establishment of the PRC opened the new chapter in the Sino–Soviet/Russian relations. For many years the existence of the problem of the common border was not openly expressed. In 1957 the first announcements about the territorial disputes between USSR and PRC were issued in China. And in 1960 Zhou Enlai stated that there were insignificant disrepancies in the Russian and Chinese maps, very easy to solve. Over the next nearly 30 years the problem of determination of the border has become a victim of tense and hostile Soviet-Chinese relations and unproductive talks. Gorbachev's rise to power in the Kremlin enabled to negotiate a solution to the Soviet–Chinese border problem. And consequently to sign “The agreement on the eastern section of the Sino-Soviet state border” on May 16, 1991. The agreement on the western section of the border was signed on September 3, 1994. The demarcation of the western section of the border was finished by Joint Russian–Chinese Demarcation Commission on September 10, 1998. After six years of negotiations on October 14, 2004 the Complementary Agreement on the Eastern Section of the China–Russia Boundary was signed in Beijing. On its basis the Russian side ceded the whole of Tarabarov island (ch. Yinlongdao), half of Bolshoy Ussuriyski (ch. Heixiazidao) and half of Bolshoy (ch. Abagaitu) island. Another halves of Bolshoy Ussuriyski and Bolshoy islands were kept by Russia. Both sides shared disputed territory almost equally. The ceremony of installation of the border landmarks between Russia and China on Bolshoy Ussuriyski island (on October 14, 2008) finished the long process of demarcation of the Russian–Chinese border.