A steel structure installed by China without due notice in the Yellow Sea where the Exclusive Economic Zones(EEZs) of South Korea and China overlap was discerned as an oil rig that had been discarded after being used in the Middle East.

The large structure, some 70 meters high and 80 meters wide, equipped with a helipad, has "Atlantic Amsterdam" written on the surface, the name of which belonged to an oil rig built by France in 1982.

Beijing claims that the latest structure supplements two previously-installed submersible structures, which it says are part of its aqua farming facility.

The allegedly fixed structure within the Provisional Maritime Zone(PMZ), where the two countries' EEZs overlap, could adversely affect Seoul's maritime boundary delimitation as the PMZ restricts activities beyond navigation and fishing.

Beijing, however, is currently obstructing Seoul's access to the area for inspection.

Officials in Seoul plan to raise the issue during a bilateral director-general-level diplomatic meeting set to take place in Seoul later this month.