Trade officials across Asia were assessing the fallout from the latest escalation in the US-China technology battle after Beijing said it would impose curbs on exports of metals used in chipmaking.South Korea’s commerce ministry convened an emergency meeting to discuss China’s decision to control exports of gallium and germanium, metals used in chips, electric vehicles and a range of telecommunication products.

“We can’t rule out the possibility of the measure being expanded to other items,” said Joo Young-joon, South Korea’s deputy commerce minister.

Japanese trade minister Yasutoshi Nishimura said Tokyo was studying the impact on its companies as well as checking Beijing’s plans for implementing the controls. Tokyo kept the door open for action at the World Trade Organization, warning that it would oppose any breach of international rules.