President Moon Jae-in told top business leaders on Wednesday that Japan’s restrictions on exports of chemicals crucial to the South Korean tech sector had caused an “unprecedented emergency.”

Last week, Tokyo said it would stop the expedited shipment of compounds used by major firms in the manufacture of microchips and smartphones, increasing long-simmering tensions over the use of forced labor during World War II.

Moon on Wednesday met executives from several companies to discuss the crisis, telling them the decision by Tokyo was intended to damage South Korea’s economy, AFP reports.

Our government “is doing its best to solve the matter diplomatically,” he said at the presidential office in Seoul. “We cannot rule out the situation will be prolonged.”