TOKYO, July 1 (Xinhua) -- The Japanese government said on Monday it will tighten restrictions on exports of high-tech materials to South Korea, citing "significant damage to the relationship of mutual trust."

The Ministry of Economy, Trade and Industry said that effective from Thursday, individual applications will be necessary for exports to South Korea of three materials used in high-tech products.

They include fluorinated polyimide, hydrogen fluoride and resist, which are used in the manufacturing process of semiconductors and screens for smartphones and TVs.

The ministry did not ban such exports outright but added screening of the applications would require about 90 days.

Relations between Japan and South Korea have soured since late last year over a series of South Korean court rulings that ordered Japanese firms to compensate laborers who were forced to work for the companies during World War II.

However, the Japanese government insists that the measure is being taken due to security concerns, adding it is not retaliation against South Korean.

According to local media, the restrictions could deal a blow to the technology industries of both countries, whose supply chains are deeply linked. The ministry said it will closely monitor the impact on Japanese companies which have a large market share of the three items.