Disputes Between the PRC and the ROK in the Yellow Sea

One of the potential flashpoints in Northeast Asia is the maritime territory disputed between the People’s Republic of China (PRC) and the Republic of Korea (ROK) in the Yellow Sea. In 2025, the situation escalated into a standoff between the coast guard vessels of the two nations.

What is the PMZ and the Background to the issue?

In 2018 and 2024, China installed two semi-submersible buoys in the PMZ. In 2022, a fixed steel structure was built, believed to be a repurposed decommissioned oil rig. Subsequently, China set up several more large steel structures (two in April and May 2024 and another in early 2025), having made the ROK apprehensive for several reasons, despite China’s insistence that these structures are intended for aquaculture.

First, the ROK claims that the steel structures installed by China could impede the passage of South Korean fishing vessels.

Second, South Korea fears that China is applying “grey-zone” tactics to expand its maritime sovereignty, similar to the construction of artificial islands carried out by Beijing in the South China Sea, where small installations were transformed into artificial islands hosting radar systems and military airstrips. The concern is that China will first build the structures, and then, under the UN Convention on the Law of the Sea, unlawfully claim maritime sovereignty based on their presence, basically turning disputed maritime areas into de facto Chinese territory.

Third, the narrative of a Chinese threat is periodically blown up by representatives of the United States. For instance, on 9 December 2025, Victor Cha, President of the Department of Geopolitics and Foreign Policy and Chair of the Korea Chair at the Center for Strategic and International Studies (CSIS), called on the United States to flag China’s installation of maritime structures in and around the jointly managed zone between South Korea and China in the Yellow Sea as yet........

© New Eastern Outlook