China restricts exports of high-tech metals in a slap at Washington ahead of Yellen’s visit

BEIJING (AP) — China has imposed export curbs on two metals used in computer chips and solar cells, expanding a squabble with Washington over high-tech trade ahead of Treasury Secretary Janet Yellen’s visit to Beijing this week. The Commerce Ministry said the restrictions on gallium and germanium are intended to “safeguard national security.” It said exports will require official permission once the rules take effect Aug. 1 but did not say what restrictions might be applied. Chinese leader Xi Jinping’s government is frustrated by U.S. restrictions on access to advanced processor chips and other technology on security grounds but has been slow to retaliate, possibly to avoid disrupting China’s fledgling tech industries.