Photo/Illutration The website of the South Korean presidential office has a section where South Koreans can enter pleas to the government to take action against tighter export regulations on semiconductor materials bound for South Korea. (Captured from website of South Korea's office of the president)

With South Korea threatening to have the World Trade Organization rule on whether new restrictions on Japanese exports of semiconductor materials constitute a violation, government officials are scrambling to come up with a rationale for their actions.

The stricter assessment on applications for the export of such materials to produce semiconductors in South Korea started July 4. Trade ministry officials clarified that the measure was only intended to avoid preferential treatment for the country, not to serve as a ban.

As a reason for the need for tighter application evaluations, the officials pointed out a number of instances of inappropriate exports regarding such materials in recent months.

High-ranking government officials also cited a precedent set in 2010 when China implemented restrictions on the export of rare earth metals to Japan. The period was one of heightened tensions between the two nations, following the acquisition of one of the disputed Senkaku Islands the previous year by the central government.

Japan had been receiving about 90 percent of such metals it used in the manufacture of automobiles and other products from China.

Facing the restriction, Japan asked the WTO to judge whether it constituted a violation of the organization's rules.

Beijing argued that the restriction should be allowed as an exception, as the General Agreement on Tariffs and Trade (GATT) recognized measures taken as part of efforts to protect the environment. However, the WTO ruled against China.

High-ranking trade ministry officials pointed out the major differences between the latest export regulations and actions taken by China almost a decade ago, saying that tighter assessments are necessary for national security reasons, as there are concerns that some of the materials could be converted for use in weapons and other military supplies.

The rare earth metals argument, however, could come back to bite Japan. After China limited such exports, Japanese companies began developing parts that required smaller amounts of such metals, and began to seek their import from other countries.

The moves led to a decline in the Chinese ratio of rare earth metal imports from about 80 percent in 2010 to about 60 percent in 2017.

Some company officials now worry that South Korean companies may take a similar step to reduce their dependence on semiconductor materials from Japan.

While this country now has about a 90-percent global share in the three materials subject to tighter regulations for exports to South Korea, the figure could drop if South Korean companies develop alternative materials.

(This article was compiled from reports by Akihiro Nishiyama, Takehiro Tomoda and Hiroki Ito.)