While striking South Korea off its whitelist of countries given special treatment in purchasing dual-use products, or products that can be used to produce weapons, Japan again cited security issues, noting the possibility of shipments to South Korea ending up in North Korea.

Seoul has repeated calls for talks to resolve the issue. But Tokyo has snubbed such calls while failing to provide any specific reasons for its export restrictions or evidence to support them.

Many here believe the restrictions are not motivated by economic or trade concerns on the South Korean part, but instead are a complicated ploy to enhance Japan's economic prowess.

"It is simply nonsense for a country that enjoys a large trade surplus to take punitive measures against a major trading partner," said Sohn Seung-pyo, a professor of international trade at Seoul's Dongguk University.

The professor said the only such case in history may be the so-called Coercive Acts taken by Britain in 1774 in the wake of the Boston Tea Party incident when Britain took a series of punitive measures against the American colonies despite its large trade surplus.

"The export restrictions are not about free trade violations nor are they about strategic materials. And Japan is apparently unable to hold bilateral meetings (with South Korea) because it has no justification for its steps," Sohn said.

Sohn suggested the Japanese move may be aimed at what he called "Korea bashing."

"Its goal may be to boost the global market share of Japanese semiconductor manufacturers because memory chips will be one of products that will benefit the most under the fourth industrial revolution," he said.

Others believe Japan's ulterior motive may be political.

Japan has repeatedly and explicitly asked Seoul to scrap two 2018 Supreme Court rulings that ordered Mitsubishi Heavy Industries to pay up to 120 million won ($101,000) each in compensation to 12 South Korean victims forced into unpaid labor for the Japanese firm during Japan's 1910-45 colonial rule of Korea.

"Japan claims the export restrictions have nothing to do with the court rulings, and says they has to do with security issues without explaining why they has to do with security issues," Kim Yong-rae, Seoul's assistant minister for trade, industry and energy, said.

"On the other hand, the Japanese government has been speaking of retaliatory measures since the Supreme Court decisions came out in November. Any normal person would think the (export restrictions and Supreme Court decisions) are related," he said in a recent telephone interview with Yonhap News Agency.

Lee Jae-cheol, an official from the state-run support group for victims of forced labor under the Japanese colonial rule, noted Tokyo may fear the possibility of tens of thousands of damage suits that may follow.

Already, about a dozen other cases are sitting at the South Korean Supreme Court, according to earlier reports.

"After the Supreme Court decision, there has been an increase in the number of bereaved families (of victims) filing damage suits. About 1,000 people have filed suits, while those who were mobilized by the Japanese government, not Japanese companies, to serve in the military, are also moving to file damage suits," Lee said.

The National Archives of Korea has a list of more than 480,000 Koreans forced into unpaid labor or sexual slavery during Japan's colonial rule of Korea. The list is based on documents, such as company payrolls and mobilization reports, provided by Japan.

In a 2012 report, South Korea's prime minister's office identified 1,439 Japanese companies that committed wartime atrocities against Koreans by forcing them into unpaid labor, 299 of which still existed and were in business as of that year.

"The Supreme Court rulings could set a precedent in damage suits that may follow in the future," a government official here said while asking not to be identified due to the sensitivity of the issue.

Seoul has warned that Japan's export curbs on South Korea will damage the economies of both South Korea and Japan by undermining South Korea's production of the two IT products -- semiconductors and displays -- along with production of the Japanese materials used in them.

The assistant trade minister insisted they will also cause "immeasurable damage" to global consumers by pushing up the prices of South Korea's two key export items, as well as all other electronic products that use them as parts.

"Nowadays, it is hard to find any electronic products that do not use those as parts, and (Japan's export restrictions) will inevitably lead to problems in global supplies of products that use DRAM semiconductors, LCD and OLED panels as parts," he said, adding South Korean OLED panels alone are used to produce some 500 million other electronic products annually.

South Korea produces about 72 percent of the global supply of DRAM semiconductors and 95 percent of OLED display panels, according to Kim.

Seoul says as much as it would like to mend its ties with Tokyo, scrapping court decisions is not possible.

"Our Supreme Court decided that the 1965 South Korea-Japan settlement agreement does not include (settlement) of inhumane crimes or human rights violations against forced laborers, and as a democratic nation, South Korea may neither ignore nor annul such a court decision," Kim Hyun-chong, a deputy chief of the National Security Office at Seoul's presidential office Cheong Wa Dae, said earlier. (Yonhap)