( CNN ) -- When President Xi Jinping arrives in Seoul this week , the Chinese leader will have passed over North Korea in favor of its arch rival . Although Beijing remains North Korea 's strongest ally , Xi is breaking with tradition by visiting South Korea first , rather than Pyongyang . `` It 's clearly a rebuff to Kim Jong Un , '' said David Kang , professor of international relations and business at the University of Southern California , referring to North Korea 's leader . Xi is expected to be in South Korea for two days to discuss trade and regional security issues , including North Korea . Trade between the two countries surpassed $ 270 billion in 2013 . And China remains South Korea 's main trading partner . Since Xi and President Park took office in their respective countries last year , the two nations have solidified a steady relationship , with several political and economic shared interests . The two have expressed similar concerns about North Korea 's nuclear ambitions in particular . Nuclear priority . Both China and South Korea pledged their commitment to denuclearize the Korean peninsula when the two heads of state met at a nuclear summit in the Netherlands in March . But this increasingly cozy relationship could be a concern for Pyongyang . On Wednesday morning , North Korea launched two short-range rockets off its east coast , according to South Korea . The secretive regime also fired `` projectiles '' into waters off its coast on Sunday and on June 26 , prompting speculation about whether North Korea was expressing displeasure with the upcoming meeting between Xi and Park . A Chinese foreign ministry spokesman said he did n't see any connection with the launches and Xi 's upcoming visit , according to Yonhap , South Korea 's semi-official news agency . With closer ties between South Korea and China , `` North Korea is worried it can be isolated in northeast Asia , '' said Kim Hankwon , director of the Center for Regional Studies at the Asan Institute for Policy Studies in Seoul . North Korea has begun talks with Japan and struck economic deals with Russia which could indicate that Kim Jong Un is trying to `` reduce dependency on China , '' he added . Pyongyang 's nuclear ambitions have tested China 's patience at times . `` Most North Korean provocations hurt China 's military and security interests , '' said Kim . `` The U.S. has increased its military and security influence over northeast Asia -- their rationale was North Korea 's nuclear threats . '' This has brought more U.S. involvement in east Asia , much to China 's chagrin . Despite Beijing 's disagreements with North Korea , there may not be much change in their decades-long alliance , Kim added . `` China is angry at North Korea 's military provocation . That does not mean that China has changed its strategy towards North Korea . '' Beijing tries to strike a balanced relationship with the Koreas , talking to the South about economic issues and the North about political topics , '' Kim said . Common ground . Apart from the issue of North Korea , China and South Korea have bonded through their distrust of Japan . `` China and South Korea share a number of issues concerning Japan including the comfort women , and the announcement of [ Japan 's Prime Minister ] Abe reinterpreting the constitution , '' said Kang , director of Korean Studies Institute at USC . On Tuesday , Japan 's Prime Minister Shinzo Abe confirmed the `` reinterpretation '' of the country 's pacifist postwar constitution , which will allow the Japanese military to assist in conflicts overseas . Both China and South Korea issued predictably chilly responses to the announcement . The two countries bitterly disagree with the way Japan has addressed its military past , especially over the issue of so-called comfort women , who were forced into sexual slavery by Japan 's imperial forces before and during World War II . Both countries are also involved in territorial disputes with Japan over the Diaoyu/Senkaku islands and Dokdo/Takeshima islands . North Korea fires two short-range rockets into sea . North Korea proposes end to hostilities with South -- with conditions . Family of woman abducted by North Korea hopes talks will bring closure .
North Korea 's president Park Geun-hye to meet with South Korean President Xi Jinping . Visit breaks tradition of Chinese leaders meeting first with China . China and South Korea enjoy closer relationship .